Mage killer

[Snappy]

After much goading, I'm finally going to DM a Pathfinder game. I decided that the best way to familiarize myself with the rules is to make characters, so I decided on one of my favorite archetypes: the Mage killer. So far, I have a fighter 4/wizard 1 human who specializes in combat maneuvers, with a sword that can cast dispel magic on command (pricey, but he's a major war veteran, so he can afford it). I have some specifics hammered out, but that's the gist of it.

However, I can't seem to find some good anti-mage combat feats (such as 3.5's Mage Slayer, Pierce Magical Concealment and Pierce Magical Protection). I checked the PFSRD, but I'm not seeing anything. Can someone suggest some good PF equivalents/alternatives?

[Spore]

Paizo's line of anti caster feats is: "Disruptive", "Spellbreaker" and to an extent "Shatterspell". That requires 10 levels of Dwarven Fighter however which is even with Steel Soul (cumulative +4 on saves vs spells and SLAs) a quite dumb route to go since you cannot threaten a flying wizard.

Arcane duelist bards get the line for free.

A few ideas would be:

An arcane archer with Arrows of Dispel Magic, Arrows of Antimagic Zone, Arrows of Fireball (even a failed save creates a big concentration check). They will suffer through levels 7-11 because their spell level will not be high enough.
A barbarian/bloodrager with the Superstitious line of Rage Powers. Bloodrager is a bit better because these can fly. If you can cram in Pounce (flying charge, pounce, dead wizard).
An inquisitor has the right tools to assassinate a Wizard in the open. Bane plus Destruction (and later on Purity) Judgments on a bow and you're good.

Don't get me started with Summoners. If the Wizard has no way to banish the Eidolon right away (and it is out since it's a 1 minute cast time) you can build a night indestructible Magic Eater. Large (later huge) Biped Eidolon with Grabbing (free grapple) Poisonous (Str poison with scaling DC) Bite (might scale up to 12d6 or 24d6 with Vital Strike) into Swallow Whole, Magical Flight (perfect maneuvers). If you still have evo points left you can pump the AC into the skies.

[Serafina]

Also worth considering is Overwatch Style (http://www.d20pfsrd.com/feats/combat-feats/overwatch-style-combat-style) (Tactician (http://www.d20pfsrd.com/feats/combat-feats/overwatch-tactician-combat), Vortex (http://www.d20pfsrd.com/feats/combat-feats/overwatch-vortex-combat)). Readied actions are pretty good at preventing spellcasters from getting off a spell, and this way you can do it at very long range.

If you go for Snap Shot (http://www.d20pfsrd.com/feats/combat-feats/snap-shot-combat) (Improved (http://www.d20pfsrd.com/feats/combat-feats/improved-snap-shot-combat)) as well, you can make use of Disruptive (http://www.d20pfsrd.com/feats/combat-feats/disruptive-combat---final) and Spellbreaker (http://www.d20pfsrd.com/feats/combat-feats/spellbreaker-combat---final) as well, if you manage to get close.
If you then play as a Crossbowman (http://www.d20pfsrd.com/classes/core-classes/fighter/archetypes/paizo---fighter-archetypes/crossbowman) Fighter you can even attack Flat-footed AC and get your Dexterity-bonus to damage - multi-class out after 11th level into Unchained Rogue to get Sneak Attack, and you'll deliver solid damage (if you have greater sniper googles at least).

[charcoalninja]

A Spell breaker Inquisition Inquisitor with maybe the snap shot line and Disruptive shot can quickly stack some serious penalties to concentration checks to cast and IIRC have a means of having their damage count as lingering. They also gain a scaling bonus to saves vs entire schools of magic which is amazing. As casters they natively have access to some anti-magic tricks.

[Ninjaxenomorph]

Weapon Master's Handbook has a few toys for a mage hunter, particularly the one that lets you use your BAB for your reflex save or for single-target effects. And fighters can get fly with Flight Mastery, though it requires UMD investment (3 ranks).

[StreamOfTheSky]

Disruptive and Spellbreaker just make an easy concentration check a bit harder. The only worthwhile anti-caster feat I know of it PF is Teleport Tactician, which is frankly not worth all the Fighter levels and garbage pre-req feats.

The best anti-caster is another caster, probably an Abjurer Wizard, but Cleric can work, too. If you want to be martially inclined, I'd look at Magus or some flavor of Bard. Or, if you were starting at a high level, Wizard 12 / Arcane Archer 2, to Imbue Arrows with Anti-magic field. You can enter AA earlier with a Fighter 1 dip into Eldritch Knight, but then you have to another level to get AMF and lose 2 more caster levels. You can take AA up to level 4 for the BAB, after that it loses another CL, so get out.

[Snappy]

So, from what I'm gathering, ranged attacks seem to be where it's at. Kinda funny, because my idea was inspired by the Mage Killer from Fate/Zero (his gun shot bullets that fried magic or something), but I didn't want to go that spot-on. Are there any other quick and dirty methods? Most NPCs in this world don't go above level 5 (exceptions exist, but are rare).

[Serafina]

For low-level, your best bet is this:
- have a good Initiative-score
- prevent the caster from ever getting a spell off
For both of those objectives, Readied Ranged Attacks are best. They use Dexterity, ensuring a high Initiative. And their range will make it more likely that you can engage the spellcaster that way.

Five levels of Fighter is just about enough room for a Human to get Overwatch Style and Tactician along with their prerequisite feats. The main effect of that would be that you get two readied actions instead of one.

But if you ready an action to attack (which sadly doesn't qualify for vital strike, by the way) "when an enemy starts casting a spell" and then hit with that attack, it's actually a rather challenging concentration-DC to cast the spell. 10+damage+spell level, so if you get more than 5 damage with the attack it will be higher than the DC to cast defensively. Better yet, a lot of effects that improve concentration checks won't apply, since they only apply to casting defensively (such as Combat Casting).
At that level, you can expect ~9 average damage. That'd call for a concentration-check of 19+spell level, so 22 for a 3rd-level spell and 20 for a 1st-level spell. A 5th-level caster would add around 10 (5 from caster level, 5 from attribute) to their check, so that'd be about a 50% chance to lose the spell (it will be higher with more damage, lower with a bad damage roll).


This actually gets better when built properly at higher levels. Do a build (https://forums.sufficientvelocity.com/posts/5835625/) with Crossbowman Fighter and Unchained Rogue, and you can throw sneak attack into the mix. Deadly Aim will help as well. The more damage, the better.
At 12th-level, you could get an average damage of ~35 damage (1D10 +2D6 sneak attack +2D6 weapon special abilities +6 from deadly aim +4 from greater sniper googles +5 from dexterity +1 from enhancement bonus). That would make for a concentration-DC of 45. With a caster level of 15, a caster would have to have another +10 to concentration checks from other sources to even have a chance of succeeding. I would like to see them try.

Of course, at higher levels you have to contend with a lot of other problems.
Casters can enter combat with active spells or summoned monsters.
Those can be rather nasty for stopping ranged attacks. Magic arrows overcome protection from arrows, you can overcome a wind wall with a cyclonic weapon (http://www.d20pfsrd.com/magic-items/magic-weapons/magic-weapon-special-abilities/cyclonic) and Improved Precise Shot will help you overcome miss chances - but you can't fully counter Blink or Mirror Image. The latter especially will ruin this tactic unless your GM allows you to make several readied attacks based on a single trigger (with four attacks, you have a decent chance of getting through mirror images) or you have access to True Seeing and the enemy is within 120 feet. But there's nothing that can neutralize blink.
If the caster gets off a wall-spell of some sort, your day will also be ruined. At least your multiple readied attacks prevent them from using swift-action casting to bypass your readied attacks, so they'd have to get the spell off first.


Is this a tactic that will neutralize high-level spellcasters?
No.
They still have tons of means of killing you without even ever engaging you. They still have tons of ways of utterly winning without fighting. They still have a bunch of options that can mostly counter your tactic.
But it'll make life for them more difficult. If they don't have specific protections and you have some preparation, you can pretty reliably prevent them from getting a spell off. They certainly won't make their concentration-checks beyond some point (damage just outscales possible bonuses to concentration). And a caster that can't even get a single spell off....well, unless that caster runs away (without spells), that caster is dead.

[charcoalninja]

Disruptive shot plus the Inquisitor ability of penalizing concentration checks on a successful ranged hit plus Disruptive Weapon of awe or some other ranged attavk is boosting the concentration DC by 8-12 and likely for more than one round. Grab a feat or MC Archer Fighter to grapple with arrows and you quickly have DCs far beyond a caster's ability to make.

I'll throw together a more specific example of what I'm talking about when I'm w/ books

Edit: you absolutely can ready an action to vital strike, I don't know where you got the idea you couldn't.

You can't use it with an attack of opportunity but after a ready to disrupt a cast is just about the best use of the feat.

[Serafina]

You can if you use the normal standard-action readying mechanic, yes.
But you can't when using Overwatch Style, since that doesn't fall under "only things that are specifically under the "attack action" can benefit from vital strike" rule that is so confusing.
Well, if you could you could eventually get up to four vital strikes per round.


Edit:
It works like this:
You can ready an action as a standard action. The action readied is either a standard action, a move action or a swift action (but it always takes a standard action to ready). Since the attack action is a specific kind of standard action, you can do that.

Overwatch Style and Vortex take a full-round action, while Overwatch Tactician takes a standard action (this part doesn't matter for whether you can use Vital Strike, mind).
However, you don't ready a standard action. You ready an attack, but that attack is not made as part of an attack action, because an attack action is this specific subset of standard actions, while attacks can come from many sources (full attacks, attacks of opportunities and so on). So while all attack actions produce attacks, not all attacks are attack actions.

Funnily enough, you could technically ready a standard action to activate Overwatch Tactician though. After all, using that feat is a standard action and you can ready any kind of standard action.

[charcoalninja]

Ah I see what's going on. Carry on!

[Snappy]

I hadn't thought about high initiative + damage before. So, my question now is, is it more worth it to make a Dex-based ranged fighter (who can get lots of feats), or should I go rogue (for stealth and sneak attack damage)?

[Serafina]

Rogues usually have difficulty applying sneak attack at range.
To do so, you basically must have a reliable method of leaving your enemy flat-footed (=denied dexterity-bonus to AC). There are very very few of those that work at range.

Sniping (attacking from stealth) works, but is unreliable (it only works as long as you are undetected), needs about two feats of investment to work properly (to not get detected after the first shot) and needs to be set up (you need to start hidden in the first place).

Surprise rounds work, but have the same problem of not working reliably, or for that matter for more than one round.

Feinting of any sort doesn't work, since it only denies the opponent their Dexterity against your next melee attack.

There are a bunch of spells that work, and a few feats that do so as well. If it blinds the enemy, it makes them flat-footed and thus you can sneak-attack. The problem is that this requires time to set up - you need one round to blind them, and only then can you actually apply sneak attack. That's one more round for the enemy to get away/get off a spell. Of course, some enemy can't be blinded either.

Making yourself Invisible is easily the most reliable method. To do this properly, you'd need Greater Invisibility.
This requires either being a caster-class, being a Ninja (who get greater invisibility as a trick at 10th level) or being an Unchained Rogue who is allowed to grab ninja master tricks (it's not on the "approved list" so you'd have to ask your GM).
Sadly it fails if the enemy has true seeing, blind sight or some other means of seeing invisible enemies.


Or you just take 7 levels in Crossbowman (http://www.d20pfsrd.com/classes/core-classes/fighter/archetypes/paizo---fighter-archetypes/crossbowman) Fighter and use readied attacks (ideally vs. Overwatch Style). Why? Because the 7th-level ability "Improved Deadshot" states that "when you attack with a crossbow as a readied action, your target is denied it's Dexterity bonus to AC".
This qualifies you for sneak attack. Now, as a Fighter you don't yet have any sneak attack - but that just means you have to take levels in Unchained Rogue or some other class that gives sneak attack after this.
And this method always works. It's not dependent on you making any preparations, it works against most enemies (the only thing that prevents it is Uncanny Dodge) and it works at range.


Now, all methods of ranged sneak attacks are also limited by the fact that you can only sneak attack within 30 feet. There are some archetypes and rogue talents that extend that range, but there's a simpler and better method: Sniper Googles (http://www.d20pfsrd.com/magic-items/wondrous-items/wondrous-items/e-g/goggles-sniper-goggles) just outright remove that limitation. They even add some extra damage, especially the greater version.



At 13th level, a Crossbowman Fighter/Bolt Ace Gunslinger/Unchained Rogue 5 can deliver 1D10+(half Dexterity, so let's say 4)+3D6+6(Deadly Shot)+6(Sniper Googles)+1(enhancement bonus) per shot, for an average of 33 damage. He can do so four times per round. These attacks target flat-footed AC and the character can spend Grit to target flat-footed touch AC if the enemy is within the first range increment (the latter basically guarantees a hit). All attacks are made at full attack bonus -2 as well, so you're basically bound to hit. Thanks to Improved Precise Shot, these attacks ignore all miss chances except total concealment and all cover except total cover. Thanks to Debilitating Injury, these attacks can also reduce enemy attacks, AC or movement speed.

Ready four attacks. Two trigger off the enemy starting to cast a spell. One triggers of enemy movement. The last triggers of the enemy getting attacked, or getting targeted by a spell (especially if you have ranged weapon trick and snap shot) - or if you're really cheesy, it triggers off an enemy taking damage (your GM may rule that only actions count, not such triggers).
This basically shuts down all actions one enemy spellcaster can take. Casting a spell will get them hit with an attack that will on average demand a DC 43 concentration check. Casting a spell as a swift action will result in the same thing (since you readied two actions against spellcasting). They can not safely move either, since it'll get them hit with another attack as well (which can halve their movement speed to boot). And depending on what you did with your fourth readied attack, it can shut down more things as well.
If there's more enemies, adjust accordingly. But at most you can simply ready four attacks against spellcasting, which can shut down four attempts at spellcasting (which can be either two enemies with swift-action casting, or up to four enemies).


Again, it's not a build that a smart spellcaster can't counter. They can still have active spells from before combat, they can still have things like emergency force sphere (although you could interrupt their immediate-action casting too) and they still have all their game-changing utility, they just can't use it near you. Mundane full cover or concealment also prevents your attacks from working, so if the enemy spellcaster is around a corner down the hallway they can summon monsters or such all they like.
But other than that, you can shut them down hard. And the build isn't useless against other characters either, you can target a fighter or archer just as well with this.

[Psyren]

Rogues usually have difficulty applying sneak attack at range.
To do so, you basically must have a reliable method of leaving your enemy flat-footed (=denied dexterity-bonus to AC). There are very very few of those that work at range.

It's a lot easier than you think - simply make sure they can't see you. At low levels, this can be as simple as hiding in the darkness (assuming you're sniping something without darkvision.) You usually can't full-attack yet anyway so the move action to restealth isn't an issue. My favored method comes only a little bit later - Fogcutting Lenses, which are only 8k and thus can be picked up as early as level 6 (or crafted yourself even before then.) Used in combination with smokesticks or an eversmoking bottle, restealthing becomes mostly irrelevant because the fog blocks line of sight completely. This method also defeats anything that pierces darkness, invisibility or illusions.

At later levels you'll have access to Greater Invisibility for the rare fights where fog doesn't work (e.g. high winds) but even then I prefer the fog method since invisibility is a counter most creatures come expecting past a certain point.

[KillingAScarab]

It's a lot easier than you think - simply make sure they can't see you. At low levels, this can be as simple as hiding in the darkness (assuming you're sniping something without darkvision.) You usually can't full-attack yet anyway so the move action to restealth isn't an issue. My favored method comes only a little bit later - Fogcutting Lenses, which are only 8k and thus can be picked up as early as level 6 (or crafted yourself even before then.) Used in combination with smokesticks or an eversmoking bottle, restealthing becomes mostly irrelevant because the fog blocks line of sight completely. This method also defeats anything that pierces darkness, invisibility or illusions.

At later levels you'll have access to Greater Invisibility for the rare fights where fog doesn't work (e.g. high winds) but even then I prefer the fog method since invisibility is a counter most creatures come expecting past a certain point.(Leomund's/Mage's) Tiny Hut (http://www.d20pfsrd.com/magic/all-spells/t/tiny-hut) should also still work in Pathfinder. It explicitly grants total coverconcealment and allows attacks to pass through it. It doesn't move, but you don't need to worry about lighting and weather.

[Ethereal Gears]

There's a Ranged Feint feat in Ultimate Intrigue that's kinda alright.

[Psyren]

(Leomund's/Mage's) Tiny Hut (http://www.d20pfsrd.com/magic/all-spells/t/tiny-hut) should also still work in Pathfinder. It explicitly grants total cover and allows attacks to pass through it. It doesn't move, but you don't need to worry about lighting and weather.

Nice trick, I didn't think of this one :smallsmile: It fits on a wand too.

[KillingAScarab]

Nice trick, I didn't think of this one :smallsmile: It fits on a wand too.Credit where it is due: I first encountered this trick (http://www.cayzle.com/screeds/book011.html) on Cayzle's Wemic site. I also just noticed I once again wrote "total cover" when I meant "total concealment," which kinda makes a difference.

[Elder_Basilisk]

Another option in Pathfinder if you want to do anti-mage stuff in melee is the step up line of feats in combination with Stand Still, combat reflexes, and disruptive. (The ranged options are good, but if you don't want to be ranged, you don't have to be).

If you can get adjacent to an enemy wizard, he is faced with a choice
A. to make a concentration check to cast defensively (at -6, so it is not an easy check before level 10, no matter what spell he's trying and is actually pretty hard if he wants to try a high level spell--Concentration DCs in pathfinder are 15 + 2x spell level and it's just caster level + attribute mod + (combat casting if you have it), so it's not nearly as easy as it is in 3.5).
B. Take a five foot step and cast. This is the usual choice, but step up lets you follow the five foot step, so he's stuck.
C. Move, take the opportunity attack damage, and then cast a spell. This is another common option since it puts the mage out of full attack range on the next turn and is normally an answer to step-up, but Stand Still means that hitting on the opportunity attack stops it cold. The mage is now down to A or D again.
D. Pull out a weapon or a wand and attack (or channel energy if a cleric).

Now you will need a ranged weapon or a potion of fly to deal with flying wizards (though the duration on fly is low enough that before overland flight enters the picture, they probably need to cast it during combat). But it is not just an anti-mage build either. It is fully effective against enemy clerics etc and can also shut down enemy archers (until they get point blank master). And at higher levels, a lot of foes such as dragons and demons have spells or spell like abilities that this will help to disrupt. And the non-disruptive elements in the build can also be effective against a variety of foes in melee (you think you'll step back and drink a potion? Not on my watch. You think you'll just take the opportunity attack and get in my wizard's face? Stand still.)

Tertori monk is another option. Grappled wizards in pathfinder are still unhappy wizards and as a tertori, their ring of freedom of movement won't help.

[13ones]

I've got a mage killer bloodrager. Iron blooded and primal archetypes. Arcane bloodline. Go drow. Build the full line of dimensional agility feats. Grab pounce from the beast totem. Dimension door as part of a charge and then full attack on said charge. Have natural Sr as well.

[Snappy]

These suggestions are a great help :) Another thing I thought about: since most spells use verbal components, and most casters I've seen don't use Silent Spell, how can one prevent a caster from speaking? I know the silence spell is best for this, but are there other ways?

[Psyren]

These suggestions are a great help :) Another thing I thought about: since most spells use verbal components, and most casters I've seen don't use Silent Spell, how can one prevent a caster from speaking? I know the silence spell is best for this, but are there other ways?

The Chokehold feat lets you stop someone you've pinned from speaking (and breathing.) You can also just knock them unconscious with nonlethal damage.

Keep in mind that to even cast they need to pass a pretty brutal concentration check, so stopping them from speaking may not even be necessary.

[Slithery D]

I want to note that Ultimate Intrigue introduces a +2 melee weapon enchantment called Truthful. It lets you ignore all illusion-based concealment chances (blur, displacement, invisibility) and always hit the real target of a Mirror Image effect. Great enchantment for someone trying to kill mages.

[Tuvarkz]

If your table allows for third party content, the Mage Hunter (http://www.d20pfsrd.com/path-of-war/prestige-classes/mage-hunter) from Path of War might be a good pick too.
You get spellcasting, both Disruptive and Spellbreaker as bonus feats, a way to prevent the enemy from teleporting away or otherwise just tag along for the teleportation, magic dispel, plus a couple stances, one that nets you stalwart/evasion, and a second stance that not only makes it so that unaware enemies may automatically fail their cast defensively checks, but also give Spell resistance, which give the character temporary hit points whenever his spell resistance blocks a spell or he saves succesfully against it.

[Feint's End]

Rogues usually have difficulty applying sneak attack at range.
To do so, you basically must have a reliable method of leaving your enemy flat-footed (=denied dexterity-bonus to AC). There are very very few of those that work at range.

Sniping (attacking from stealth) works, but is unreliable (it only works as long as you are undetected), needs about two feats of investment to work properly (to not get detected after the first shot) and needs to be set up (you need to start hidden in the first place).

Surprise rounds work, but have the same problem of not working reliably, or for that matter for more than one round.

Feinting of any sort doesn't work, since it only denies the opponent their Dexterity against your next melee attack.

There are a bunch of spells that work, and a few feats that do so as well. If it blinds the enemy, it makes them flat-footed and thus you can sneak-attack. The problem is that this requires time to set up - you need one round to blind them, and only then can you actually apply sneak attack. That's one more round for the enemy to get away/get off a spell. Of course, some enemy can't be blinded either.

Making yourself Invisible is easily the most reliable method. To do this properly, you'd need Greater Invisibility.
This requires either being a caster-class, being a Ninja (who get greater invisibility as a trick at 10th level) or being an Unchained Rogue who is allowed to grab ninja master tricks (it's not on the "approved list" so you'd have to ask your GM).
Sadly it fails if the enemy has true seeing, blind sight or some other means of seeing invisible enemies.


Or you just take 7 levels in Crossbowman (http://www.d20pfsrd.com/classes/core-classes/fighter/archetypes/paizo---fighter-archetypes/crossbowman) Fighter and use readied attacks (ideally vs. Overwatch Style). Why? Because the 7th-level ability "Improved Deadshot" states that "when you attack with a crossbow as a readied action, your target is denied it's Dexterity bonus to AC".
This qualifies you for sneak attack. Now, as a Fighter you don't yet have any sneak attack - but that just means you have to take levels in Unchained Rogue or some other class that gives sneak attack after this.
And this method always works. It's not dependent on you making any preparations, it works against most enemies (the only thing that prevents it is Uncanny Dodge) and it works at range.


Now, all methods of ranged sneak attacks are also limited by the fact that you can only sneak attack within 30 feet. There are some archetypes and rogue talents that extend that range, but there's a simpler and better method: Sniper Googles (http://www.d20pfsrd.com/magic-items/wondrous-items/wondrous-items/e-g/goggles-sniper-goggles) just outright remove that limitation. They even add some extra damage, especially the greater version.



At 13th level, a Crossbowman Fighter/Bolt Ace Gunslinger/Unchained Rogue 5 can deliver 1D10+(half Dexterity, so let's say 4)+3D6+6(Deadly Shot)+6(Sniper Googles)+1(enhancement bonus) per shot, for an average of 33 damage. He can do so four times per round. These attacks target flat-footed AC and the character can spend Grit to target flat-footed touch AC if the enemy is within the first range increment (the latter basically guarantees a hit). All attacks are made at full attack bonus -2 as well, so you're basically bound to hit. Thanks to Improved Precise Shot, these attacks ignore all miss chances except total concealment and all cover except total cover. Thanks to Debilitating Injury, these attacks can also reduce enemy attacks, AC or movement speed.

Ready four attacks. Two trigger off the enemy starting to cast a spell. One triggers of enemy movement. The last triggers of the enemy getting attacked, or getting targeted by a spell (especially if you have ranged weapon trick and snap shot) - or if you're really cheesy, it triggers off an enemy taking damage (your GM may rule that only actions count, not such triggers).
This basically shuts down all actions one enemy spellcaster can take. Casting a spell will get them hit with an attack that will on average demand a DC 43 concentration check. Casting a spell as a swift action will result in the same thing (since you readied two actions against spellcasting). They can not safely move either, since it'll get them hit with another attack as well (which can halve their movement speed to boot). And depending on what you did with your fourth readied attack, it can shut down more things as well.
If there's more enemies, adjust accordingly. But at most you can simply ready four attacks against spellcasting, which can shut down four attempts at spellcasting (which can be either two enemies with swift-action casting, or up to four enemies).


Again, it's not a build that a smart spellcaster can't counter. They can still have active spells from before combat, they can still have things like emergency force sphere (although you could interrupt their immediate-action casting too) and they still have all their game-changing utility, they just can't use it near you. Mundane full cover or concealment also prevents your attacks from working, so if the enemy spellcaster is around a corner down the hallway they can summon monsters or such all they like.
But other than that, you can shut them down hard. And the build isn't useless against other characters either, you can target a fighter or archer just as well with this.

Where do you get the rules for readied actions from? AFAIK you can only spend a standard action and ready a standard action (meaning 1 attack in most cases unless you get a way to attack more often in a standard action).

[Serafina]

Yes, normally. That's why you take Overwatch Style and it's follow-up feats:
Overwatch Style (http://www.d20pfsrd.com/feats/combat-feats/overwatch-style-combat-style): As a full-round action, you can ready two attacks with a ranged weapon, each with it's own triggering event. These attacks take a -2 penalty to their attack rolls.
Overwatch Tactician (http://www.d20pfsrd.com/feats/combat-feats/overwatch-tactician-combat): Now it can be done as a standard action.
Overwatch Vortex (http://www.d20pfsrd.com/feats/combat-feats/overwatch-vortex-combat): As a full-round action, but with four readied attacks.

Now, there's some debate whether "each with their own triggering event" language precludes you from choosing the same trigger for multiple readied attacks. IIRC the most common solution is "you can totally do that, but you can only trigger one attack per singular triggering event". So you could ready two attacks with "when an enemy starts casting a spell" as a trigger, but when an enemy actually does start casting one you'll only make one attack. If however the same trigger occurs from a different source (someone else starts casting, or the same creature starts casting via swift-action casting) the other readied attack would go off.

Now, Readied Actions as a whole can be cheesed a lot. You just have to specify a "condition" and it doesn't specify anywhere what that could be. So you could do something cheesy and simply go with "attack once an enemy takes an action of any sort", "attack once an enemy gets targeted by one of my attacks", "attack once an enemy gets hit by one of my attacks" and "attack once an enemy takes damage by one of my attacks", or something to that effect, to simply attack one enemy four times. That's the point where (absent an official ruling) the GM simply has to say "no" and impose some limitations on it. Something simple such as this:
- each "condition" must either be the taking of an action (somebody attacks or moves or tries to cast a spell) or the result of an action (somebody gets hit or cursed or knocked prone)
- a "condition" can not occur as the result of a characters own actions. An enemy getting hit by the attack of another character is a valid trigger, an enemy getting hit (or wounded) by your own attack is not
- you may choose the same wording for multiple readied attacks (such as choosing "an enemy moves" twice) but each "condition" will only trigger one attack (so if you have two "when an enemy starts to cast a spell, only one attack will trigger if an enemy casts a spell, while the other will still be readied).
- each "condition" can specify it's target in both specific and general terms. "An enemy", "the ogre chieftain" or "these three of my allies" are all valid. If a "condition" specifies a target, it must also be the target of the resulting action or attack

Mind you, that's just how I'd handle things to prevent shenanigans.
Mind you, at worst those shenanigans would only be four attacks, as a full-round action, or two attack as a standard action. That's nothing broken, even if you build for targeting flat-footed AC and apply sneak-attack to it (there are other ways to do that after all). The worst part would be forcing an enemy spellcaster to make four concentration-checks (due to hitting them four times), but at that point one attack should do enough damage that it'll disrupt the spell anyway.

[Vogie]

These suggestions are a great help :) Another thing I thought about: since most spells use verbal components, and most casters I've seen don't use Silent Spell, how can one prevent a caster from speaking? I know the silence spell is best for this, but are there other ways?

Since we're in Pathfinder, a Called Shot to the Neck will either hamper spellcasting or remove that ability for a period of time.

[Snappy]

Since we're in Pathfinder, a Called Shot to the Neck will either hamper spellcasting or remove that ability for a period of time.

I looked into that, but called shots there seem too unreliable to be effective. A -10 to hit that will usually result in a 20% failure rate (unless you crit) is too risky a strategy, unless there's something I'm forgetting, or some way to make it easier to use.

[Feint's End]

Thanks for clarifying Serafina.

Looks like an interesting style. Might try to use it myself sometime.