strangebloke
2018-02-17, 12:35 PM
Fishing For Crits
http://cdn1-www.playstationlifestyle.net/assets/uploads/2012/07/massivedamage_feature.jpeg
flip it on its back, attack it's weak point, and deal massive critical damage
Abstract:
Crits. they feel good, amiright? But what if you could have them more often? What if you could make them deal even more damage. This guide explores the methods of getting more crits and how to make those crits better.
Throughout, I'll be using the following key:
Superior
Decent
Suboptimal
Wait, wait, hold on, is Crit-fishing really viable?
Everyone knows that crits deal a lot of damage. Crits increase your damage output on an attack somewhere between 30% and 100%, but a lot of people say "Oh, come on, you're only going to be getting a crit on 1/20 or 2/20 rolls, that's not that reliable." In one sense, they're right. The highest chance you can get per roll is 3/20, or about 15%. However, with various features you can raise the number of rolls you make per attack. A 15th level champion with elven accuracy has a crit-chance per attack of 38%!
And actually, that's still somewhat misleading, because crit-chance-per-attack isn't really directly connected to DPR. For that, you'll need to look at crit-chance-per-hit. I'll explain this with an example. Let's say that champion fighter up above needs to roll a 13 or higher to actually hit his enemy. He has a 78% chance of hitting him, and a 38% of critting. On the 22% of times that he does not hit, he will deal no damage. On the 38% of times where he crits, he'll deal close to double damage. Lets say he does not have GWM, but has a flaming greatsword that averages 15 damage on a hit.
expected damage without crits: 0.78*15 = 11.7
expected crit bonus damage: 0.38*15 = 5.7
In other words, crits account for fully a third of this character's damage. Therefore critfishing forms a large proportiopnal part of his damage. And this is without using crit-on-demand abilities like assassinate or hold person. Most importantly, however, crits feel great and are very fun. There is a slight problem with crit-fishing, in that a lot of times you'll 'waste' a bunch of damage on a weak target, but in my experience, obliterating a goblin with 75 damage is still tons of fun.
The other thing to note here is that crit-fishing is something you get better returns on the more that you build into it. If you're not getting advantage and don't have any way to deal extra damage on a crit (smite, brutal critical) the champion 3 feature is actually worse than an ASI.
Notes
1. I'm not looking at UA at this time.
2. This is a practical guide to crit-fishing, not a theoretical discussion of the maximum crit damage you can get. That particular discussion has been done to death. The answer, by the way, is Bugbear vPally 3, Assassin 17, wielding a rapier and using Booming Blade through Magic initiate.
3. I'm not considering magic items. Going champion 15 makes a lot more sense if you have a flaming greatsword, but we're pretending that you don't.
4. As with everything in 5e, builds get better with teamwork. It's a lot more practical to ask your wizard to cast hold person than it is to try and fit 3 levels of wizard into your barbarian build.
Quick Version
Race
There are three races that offer bonuses to crit-based builds. You don't have to pick one of these, but they are the best options.
Bugbear: Get's 2d6 damage against surprised enemies. The logical choice if you are picking up assassin levels
Elf(any type): Let's you get elven accuracy which is a great crit-fishing feat and a great feat in general. Logical for dex-based crit-fishers.
Orc/Half-Orc: Bonus damage to crits based off of weapon die size. Good for STR-based crit-fishers.
Class
Paladin/Whispers Bard/Hexblade: Adds lots of damage after you crit. These abilities are twice as valuable for a crit-focused build as they are normally. Paladin breaks at 2 or 5 for our purposes(6 is also a breakpoint).
Hexblade:. Gives you a means of fishing for crits if you're DEX-based. Adds lots of damage after you crit. Multiclass away after 1, 5, 9, or 11.
Sorcerer: Can quicken hold person and then run in and get automatic criticals in melee.
Assassin: Automatic criticals in a surprise round, and most of your damage comes from dice. Multiclass away after lvl 3 or not at all if you want SA damage.
Barbarian: makes crits hit harder if you're willing to invest a lot of levels.
Champion: makes crits more frequent. Ideal for either DEX-based or STR-based fishing. Generally more than 3 levels is not a good idea.
Intuitive multiclasses include champion/barbarian, any combination of those incestuous CHA-based casters, or Assassin/Barbarian.
Maximizing Crit Chance:
https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcQDYURjBREDfOH3F6gXUcSbw_XOoEmgF p-VevwL-WTOGE6Tt4Yk
Disadvantage: because real men earn their crits
Expand the Crit Range
In 3x every weapon had it's own crit range. In 5e, everything is 20 by default and there are only a few abilities that increase chance, which means we definitely want them:
Improved Critical(Champion Fighter 3): You're wielding a weapon? Good. You have more crits. No actions used, no resources expended. Very strong. Requires a three-level dip, but then, Champion 3 is a sensible dip for many characters.
Hexblade's Curse(Hexblade Warlock 1): Requires a bonus action to activate and it's only against one target and it's only once per short rest and since you're going hexblade it doesn't make sense to use anything other than a longsword or rapier... but it only requires a one level dip and it's incredibly synergistic with Sorcerers, paladins, etc. Strictly worse than Improved Critical for our purposes.
Superior Critical(Champion Fighter 15): On the one hand this takes the awesomeness of Champion 3 and makes it better. On the other hand, you have to go all the way to Champion 15. This is the only way to get an 18-20 crit chance.
Invincible Conqueror(Conquest 20): get's you to 19-20 for a full minute. Only works on melee weapon attacks, making it by far the weakest of the options for our purposes.
Rerolls for Days
So, if you can only make your chances on any given roll so high, the obvious next step is to make more rolls.
More Attacks(various): I talk about crit-chance per attack, but obviously if you get more attacks your chances can skyrocket. Two-Weapon fighting, Haste, the extra attack feature, the Gloomstalker's dread ambusher ability... they're all covered here. That said, some classes that give lots of attacks (like the fighter) don't really give you that much bonus crit damage, so be wary.
Advantage(mechanic):This is a huge boost to your crit chance, and all you have to do is... well, it varies. There's lots of ways of getting advantage consistently. Some examples include a familiar, Reckless Attack, darkness+devil's sight, and flanking.
Elven Accuracy(feat): Cons are that you gotta spend half a feat, meet a minimum standard of elfishness, use a non-STR-based weapon, and then find a way to get advantage. Pros are that your crit chance increases by a wide margin.
Lucky(feat): a great feat in general, and you can use it to boost your crit chances, by turning disadvantage into double advantage. Over the course of a day the effect isn't that great, however, and there are better usages of this ability.
Lucky(Halfling): is a fine feature that gives a *tiny* (<1%) bonus to your chances on each attack. It also doesn't really combine well with advantage.
Master Duelist(Swashbuckler 17): Once per short rest, you get to reroll if you're using the right sort of weapon and... yeah, it's better than halfling luck, worse than almost anything else for our purposes.
Stalker's Flurry(Gloom Stalker 11): As 'master duelist' but once per turn. Not nearly as good as elven accuracy, but it works with all weapons, and against a high AC opponent it's pretty nice.
Alternately, Don't Roll At all
There are a variety of bonuses that just give you a free crit.
Hold Person/Hold Monster: Any attack made from 5 feet away against a paralyzed target that hits is an automatic crit. Note that although you'll have advantage, you do still need to actually hit the guy. Very good, but unless you have three levels in sorcerer you'll usually want a friend to cast this for you.
Sleep/Unconscious: Don't let sleeping dogs lie, hit them before they bite you! This is a good method at low levels, but if you can get them while asleep, you should be able to win regardless.
Portent(Diviner 2): You don't even roll a d20! The Diviner just hands you a crit and you roll for damage (terrible, terrible damage). This feels very strong, but most of the time this isn't the best usage of the ability and it can only give you at most a crit or two per day.
Assassinate:All attacks against a surprised foe are crits. Self-explanatory and great.
Maximizing Crit Damage:
https://orig00.deviantart.net/5b02/f/2012/232/4/3/boom__headshot_by_animations4you-d5btnow.gif
Boom, Headshot
Stuff That Gives Extra Damage, (But Only When You Crit)
These abilities were balanced with the assumption that you'd have at best a 10% crit chance. Since we'll be getting crits much more often than that, they're better for us than they are for everyone else.
Brutal Critical(Barbarian 9,13,17): 1 extra damage die of the same type as whatever your weapon deals. This is great, but unfortunately it doesn't get started until quite late.
Savage Attacks(Half-Orc): Same as Barbarian 9, and stacks with it. Note: when you can get a 9th level feature at level 1, that's a good thing. The only drawback is that being a half-orc means you can't qualify for elven accuracy (half-orc/half-elf=OP?) but that's fine if you're STR-based. Works best with a Greataxe.
Divine Smite/Eldritch Smite(Paladin 2, Hexblade 5): OK, so these are different features and you can use them when you don't crit. Since we'll be critting so often, though, the value of these (already stellar) abilities is doubled. You can use both smites on the same attack, expending two spells to do so, but that's probably overkill. (just kidding, overkill doesn't exist.)
Superiority Dice(Battlemaster 3): Once again, you can technically use this when you're not critting, although I don't know why. Then again, you chose to go BM for a crit-fishing build so anything is on the table, really. Not a huge bonus, but it is a positive. Other classes get superiority die or an equivalent. (swords bard) They're all mediocre for our purposes.
Arcane Shot(Arcane Archer 3): a little bit better than superiority dice for our purposes. Gets much better at level 18, but we all know that isn't a real place.
Orcish Fury(feat): Can't take it if you're a full orc! But yeah, add another weapon damage die 1/short rest. If you add it after you cit, you get two weapon damage die so clearly that's what you're always going to do. A small bonus, but it's half of a half-feat so what did you expect?
Psychic Daggers(Whispers Bard 3): Bard smite! 4-5 times per short rest, so you can use it on a non-crit but you won't.
Stuff That Gives Extra Damage, (And Plays Nicely with Crits)
Self-explanatory. You want damage that comes in the form of more dice as opposed to damage that comes in the form of flat bonuses. You also want stuff associated with weapon attacks, since that's where your expanded crit range comes into play. There's a ton of good examples here since nearly every class has some way to add dice, but I'm going to talk about the stand-out options. Many of these are great spells and abilities, but I'm ranking them on the basis of how much better they make us at critting.
Sneak Attack(Rogue 1): A fistful or two (or three or four) of d6 goes a long ways. Pure, dice-based damage. Only works with finesse weapons but can be used in a str build if you have a way of getting heavy/medium armor.
Green-Flame Blade and Booming Blade(Cantrip,SCAG): Both of the effects that increase crit range require weapon attacks, so unless you're using portent/hold person, this is probably your best way to crit with a cantrip.
Shadow Blade(Wizard Spell,XGtE): You get a finesse weapon that deals 2-5 times as many die as a rapier, depending on high you upcast it. Fantastic.
Holy Weapon(Cleric Spell, XGtE): Shadow Blade's older, less edgy cousin. It's a buff to your weapon and not a new weapon, so if you have a vicious flametongue greatsword this is much better than Shadow Blade. Lasts a full hour.
Hunter's Mark/Hex(Ranger/Warlock Spell): As close to free bonus dice as you can get without actually being free.
Improved Divine Smite(Paladin 11):Is actually free. Funny how paladins keep coming up here.
Ambush(Bugbear, VGtM):2d6 damage per attack against a surprised enemy. Nice. Unfortunately means that you can't be a half-orc or elf. (Half-Orc/Half-Elf, but raised by Bugbears=OP?)
GWF(Fighting Style):If your DM doesn't pay attention to erratta, this is awesome. By RAW, GWF adds about .67 on average to each die you roll, so long as your attack involves a heavy weapon. Even with Errata, you'll get .67 per weapon damage die, which can still be pretty great for a high-level half-orc barbarian and his 8d12 crit damage.
Savage Attacker(Feat):Reroll damage on all your weapon damage in a single attack, once per turn. This feat was made for a crit-fishing build! Unfortunately, this feat was made poorly. On 8d12, you'll get a damage buff of ~6. On 1d12 you'll get ~2. Decent by itself, but given the investment it is underwhelming for us.
Dread Ambusher/Colossus Slayer/Planar Warrior:(Ranger 3): Most of the ranger subclasses get a few extra damage die. Decent.
Divine Fury(Zealot 3): A free d6 is always welcome.
There are also a lot of 'smite spells' as well as things like zephyr strike, which will buy you a few d8s and d6s here and there, but they're all very similar (not great) for our purposes so I won't call them out individually.
Are GWM/Sharpshooter bad for a crit-fishing build?
Well, no. If you roll a crit, you're going to hit pretty much regardless of the -5 or not. In fact, because both critfishing and GWM/SS require you to find advantage, these abilities work pretty well with each other. GWM in particular give an extra attack on each crit, which is insane. for builds like this.
Builds:
Feats: Sharpshooter.
Not a crit-fisher, not really, but it has absurd crit damage, and a decent way to get crits. You can hit people from an absurd distance, you're invisible in the dark, you have expertise in stealth, and if you surprise an enemy, you get an automatic critical and deal silly damage. Death Strike lets you double damage against a target.
crit chance per attack:100% (while attacking a surprised target. Otherwise 10%)
Crit Damage:(2d8 (longbow) + 5(DEX) + 18d6(sneak attack) + 4d6(Ambush) + 2d8(dread ambusher) + 2d6(hunter's mark) + 10(SS)) * 2 = 228.
Is it practical? Sorta. You're probably better off going for two more levels in gloom stalker though. Few games make it to tier 4.
resources needed for listed damage? 1 first-level spell, surprise.
Feats:Orc Fury, Savage attacker, GWM.
Lays down fat crits. I know I said earlier that overkill doesn't exist, but in all seriousness it's a problem for this poor guy. You go up to bash a goblin and then you accidentally deal a hundred damage. Good news is, he doesn't really need to expend resources to hurt things. Even better news is that unlike the other two builds listed here, he can get 2-3 attacks off a turn, so he's much more consistent and his DPR is much higher than the numbers suggest.
Crit Chance Per Attack: 19%
Crit Damaget: 2d12 (greataxe) + 5(STR) + 3d12(Brutal Critical) + 1d12 (Savage Attacks) + 2d12(Orcish Fury) + 2d6 + 10(Divine Fury) + 5.5 (Savage Attacker) + 5.3 (GWF) + 4(rage damage) + 10 (GWM)= 99
Is it practical? Yup! You can easily dump Savage Attacker from this build, but otherwise this is a very tough, effective build. Playing a zealot isn't really required here, any barbarian will do.
resources needed for listed damage? 1 short rest ability (orcish fury) and 1 usage of rage.
Feats: Elven Accuracy, Magic initiate:Wizard(find familiar)
Ivocations:Eldritch Smite, Thirsting Blade, lifedrinker
You too can live a breaking benjamin song! Hexblade's curse expands your range, your familiar gives you one source of advantage and leaves your concentration free. Or you can just skip the fishing and quicken hold person before running in. Your call.
Crit Chance per Attack: 27%
Crit Damage: 2d8(longsword) +5(CHA) + 10d8 (smite)+ 10d8 (eldritch smite) + 2 (dueling) +8d8 (GFB/BB) = 142
Is it practical? Sure. However, bursts like the one shown above consume too many resources, so you're probably better off with a more stable sorcadin build. Note that twinning and quickening the blade attack cantrips is a really good way to fish for crits, since you can get up to four cantrips in a turn (not targeted at one person, however.) Note that you're also kinda low on HP.
resources needed for listed damage? Hexblade's curse(1/sr), 2 4th level spells.
http://cdn1-www.playstationlifestyle.net/assets/uploads/2012/07/massivedamage_feature.jpeg
flip it on its back, attack it's weak point, and deal massive critical damage
Abstract:
Crits. they feel good, amiright? But what if you could have them more often? What if you could make them deal even more damage. This guide explores the methods of getting more crits and how to make those crits better.
Throughout, I'll be using the following key:
Superior
Decent
Suboptimal
Wait, wait, hold on, is Crit-fishing really viable?
Everyone knows that crits deal a lot of damage. Crits increase your damage output on an attack somewhere between 30% and 100%, but a lot of people say "Oh, come on, you're only going to be getting a crit on 1/20 or 2/20 rolls, that's not that reliable." In one sense, they're right. The highest chance you can get per roll is 3/20, or about 15%. However, with various features you can raise the number of rolls you make per attack. A 15th level champion with elven accuracy has a crit-chance per attack of 38%!
And actually, that's still somewhat misleading, because crit-chance-per-attack isn't really directly connected to DPR. For that, you'll need to look at crit-chance-per-hit. I'll explain this with an example. Let's say that champion fighter up above needs to roll a 13 or higher to actually hit his enemy. He has a 78% chance of hitting him, and a 38% of critting. On the 22% of times that he does not hit, he will deal no damage. On the 38% of times where he crits, he'll deal close to double damage. Lets say he does not have GWM, but has a flaming greatsword that averages 15 damage on a hit.
expected damage without crits: 0.78*15 = 11.7
expected crit bonus damage: 0.38*15 = 5.7
In other words, crits account for fully a third of this character's damage. Therefore critfishing forms a large proportiopnal part of his damage. And this is without using crit-on-demand abilities like assassinate or hold person. Most importantly, however, crits feel great and are very fun. There is a slight problem with crit-fishing, in that a lot of times you'll 'waste' a bunch of damage on a weak target, but in my experience, obliterating a goblin with 75 damage is still tons of fun.
The other thing to note here is that crit-fishing is something you get better returns on the more that you build into it. If you're not getting advantage and don't have any way to deal extra damage on a crit (smite, brutal critical) the champion 3 feature is actually worse than an ASI.
Notes
1. I'm not looking at UA at this time.
2. This is a practical guide to crit-fishing, not a theoretical discussion of the maximum crit damage you can get. That particular discussion has been done to death. The answer, by the way, is Bugbear vPally 3, Assassin 17, wielding a rapier and using Booming Blade through Magic initiate.
3. I'm not considering magic items. Going champion 15 makes a lot more sense if you have a flaming greatsword, but we're pretending that you don't.
4. As with everything in 5e, builds get better with teamwork. It's a lot more practical to ask your wizard to cast hold person than it is to try and fit 3 levels of wizard into your barbarian build.
Quick Version
Race
There are three races that offer bonuses to crit-based builds. You don't have to pick one of these, but they are the best options.
Bugbear: Get's 2d6 damage against surprised enemies. The logical choice if you are picking up assassin levels
Elf(any type): Let's you get elven accuracy which is a great crit-fishing feat and a great feat in general. Logical for dex-based crit-fishers.
Orc/Half-Orc: Bonus damage to crits based off of weapon die size. Good for STR-based crit-fishers.
Class
Paladin/Whispers Bard/Hexblade: Adds lots of damage after you crit. These abilities are twice as valuable for a crit-focused build as they are normally. Paladin breaks at 2 or 5 for our purposes(6 is also a breakpoint).
Hexblade:. Gives you a means of fishing for crits if you're DEX-based. Adds lots of damage after you crit. Multiclass away after 1, 5, 9, or 11.
Sorcerer: Can quicken hold person and then run in and get automatic criticals in melee.
Assassin: Automatic criticals in a surprise round, and most of your damage comes from dice. Multiclass away after lvl 3 or not at all if you want SA damage.
Barbarian: makes crits hit harder if you're willing to invest a lot of levels.
Champion: makes crits more frequent. Ideal for either DEX-based or STR-based fishing. Generally more than 3 levels is not a good idea.
Intuitive multiclasses include champion/barbarian, any combination of those incestuous CHA-based casters, or Assassin/Barbarian.
Maximizing Crit Chance:
https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcQDYURjBREDfOH3F6gXUcSbw_XOoEmgF p-VevwL-WTOGE6Tt4Yk
Disadvantage: because real men earn their crits
Expand the Crit Range
In 3x every weapon had it's own crit range. In 5e, everything is 20 by default and there are only a few abilities that increase chance, which means we definitely want them:
Improved Critical(Champion Fighter 3): You're wielding a weapon? Good. You have more crits. No actions used, no resources expended. Very strong. Requires a three-level dip, but then, Champion 3 is a sensible dip for many characters.
Hexblade's Curse(Hexblade Warlock 1): Requires a bonus action to activate and it's only against one target and it's only once per short rest and since you're going hexblade it doesn't make sense to use anything other than a longsword or rapier... but it only requires a one level dip and it's incredibly synergistic with Sorcerers, paladins, etc. Strictly worse than Improved Critical for our purposes.
Superior Critical(Champion Fighter 15): On the one hand this takes the awesomeness of Champion 3 and makes it better. On the other hand, you have to go all the way to Champion 15. This is the only way to get an 18-20 crit chance.
Invincible Conqueror(Conquest 20): get's you to 19-20 for a full minute. Only works on melee weapon attacks, making it by far the weakest of the options for our purposes.
Rerolls for Days
So, if you can only make your chances on any given roll so high, the obvious next step is to make more rolls.
More Attacks(various): I talk about crit-chance per attack, but obviously if you get more attacks your chances can skyrocket. Two-Weapon fighting, Haste, the extra attack feature, the Gloomstalker's dread ambusher ability... they're all covered here. That said, some classes that give lots of attacks (like the fighter) don't really give you that much bonus crit damage, so be wary.
Advantage(mechanic):This is a huge boost to your crit chance, and all you have to do is... well, it varies. There's lots of ways of getting advantage consistently. Some examples include a familiar, Reckless Attack, darkness+devil's sight, and flanking.
Elven Accuracy(feat): Cons are that you gotta spend half a feat, meet a minimum standard of elfishness, use a non-STR-based weapon, and then find a way to get advantage. Pros are that your crit chance increases by a wide margin.
Lucky(feat): a great feat in general, and you can use it to boost your crit chances, by turning disadvantage into double advantage. Over the course of a day the effect isn't that great, however, and there are better usages of this ability.
Lucky(Halfling): is a fine feature that gives a *tiny* (<1%) bonus to your chances on each attack. It also doesn't really combine well with advantage.
Master Duelist(Swashbuckler 17): Once per short rest, you get to reroll if you're using the right sort of weapon and... yeah, it's better than halfling luck, worse than almost anything else for our purposes.
Stalker's Flurry(Gloom Stalker 11): As 'master duelist' but once per turn. Not nearly as good as elven accuracy, but it works with all weapons, and against a high AC opponent it's pretty nice.
Alternately, Don't Roll At all
There are a variety of bonuses that just give you a free crit.
Hold Person/Hold Monster: Any attack made from 5 feet away against a paralyzed target that hits is an automatic crit. Note that although you'll have advantage, you do still need to actually hit the guy. Very good, but unless you have three levels in sorcerer you'll usually want a friend to cast this for you.
Sleep/Unconscious: Don't let sleeping dogs lie, hit them before they bite you! This is a good method at low levels, but if you can get them while asleep, you should be able to win regardless.
Portent(Diviner 2): You don't even roll a d20! The Diviner just hands you a crit and you roll for damage (terrible, terrible damage). This feels very strong, but most of the time this isn't the best usage of the ability and it can only give you at most a crit or two per day.
Assassinate:All attacks against a surprised foe are crits. Self-explanatory and great.
Maximizing Crit Damage:
https://orig00.deviantart.net/5b02/f/2012/232/4/3/boom__headshot_by_animations4you-d5btnow.gif
Boom, Headshot
Stuff That Gives Extra Damage, (But Only When You Crit)
These abilities were balanced with the assumption that you'd have at best a 10% crit chance. Since we'll be getting crits much more often than that, they're better for us than they are for everyone else.
Brutal Critical(Barbarian 9,13,17): 1 extra damage die of the same type as whatever your weapon deals. This is great, but unfortunately it doesn't get started until quite late.
Savage Attacks(Half-Orc): Same as Barbarian 9, and stacks with it. Note: when you can get a 9th level feature at level 1, that's a good thing. The only drawback is that being a half-orc means you can't qualify for elven accuracy (half-orc/half-elf=OP?) but that's fine if you're STR-based. Works best with a Greataxe.
Divine Smite/Eldritch Smite(Paladin 2, Hexblade 5): OK, so these are different features and you can use them when you don't crit. Since we'll be critting so often, though, the value of these (already stellar) abilities is doubled. You can use both smites on the same attack, expending two spells to do so, but that's probably overkill. (just kidding, overkill doesn't exist.)
Superiority Dice(Battlemaster 3): Once again, you can technically use this when you're not critting, although I don't know why. Then again, you chose to go BM for a crit-fishing build so anything is on the table, really. Not a huge bonus, but it is a positive. Other classes get superiority die or an equivalent. (swords bard) They're all mediocre for our purposes.
Arcane Shot(Arcane Archer 3): a little bit better than superiority dice for our purposes. Gets much better at level 18, but we all know that isn't a real place.
Orcish Fury(feat): Can't take it if you're a full orc! But yeah, add another weapon damage die 1/short rest. If you add it after you cit, you get two weapon damage die so clearly that's what you're always going to do. A small bonus, but it's half of a half-feat so what did you expect?
Psychic Daggers(Whispers Bard 3): Bard smite! 4-5 times per short rest, so you can use it on a non-crit but you won't.
Stuff That Gives Extra Damage, (And Plays Nicely with Crits)
Self-explanatory. You want damage that comes in the form of more dice as opposed to damage that comes in the form of flat bonuses. You also want stuff associated with weapon attacks, since that's where your expanded crit range comes into play. There's a ton of good examples here since nearly every class has some way to add dice, but I'm going to talk about the stand-out options. Many of these are great spells and abilities, but I'm ranking them on the basis of how much better they make us at critting.
Sneak Attack(Rogue 1): A fistful or two (or three or four) of d6 goes a long ways. Pure, dice-based damage. Only works with finesse weapons but can be used in a str build if you have a way of getting heavy/medium armor.
Green-Flame Blade and Booming Blade(Cantrip,SCAG): Both of the effects that increase crit range require weapon attacks, so unless you're using portent/hold person, this is probably your best way to crit with a cantrip.
Shadow Blade(Wizard Spell,XGtE): You get a finesse weapon that deals 2-5 times as many die as a rapier, depending on high you upcast it. Fantastic.
Holy Weapon(Cleric Spell, XGtE): Shadow Blade's older, less edgy cousin. It's a buff to your weapon and not a new weapon, so if you have a vicious flametongue greatsword this is much better than Shadow Blade. Lasts a full hour.
Hunter's Mark/Hex(Ranger/Warlock Spell): As close to free bonus dice as you can get without actually being free.
Improved Divine Smite(Paladin 11):Is actually free. Funny how paladins keep coming up here.
Ambush(Bugbear, VGtM):2d6 damage per attack against a surprised enemy. Nice. Unfortunately means that you can't be a half-orc or elf. (Half-Orc/Half-Elf, but raised by Bugbears=OP?)
GWF(Fighting Style):If your DM doesn't pay attention to erratta, this is awesome. By RAW, GWF adds about .67 on average to each die you roll, so long as your attack involves a heavy weapon. Even with Errata, you'll get .67 per weapon damage die, which can still be pretty great for a high-level half-orc barbarian and his 8d12 crit damage.
Savage Attacker(Feat):Reroll damage on all your weapon damage in a single attack, once per turn. This feat was made for a crit-fishing build! Unfortunately, this feat was made poorly. On 8d12, you'll get a damage buff of ~6. On 1d12 you'll get ~2. Decent by itself, but given the investment it is underwhelming for us.
Dread Ambusher/Colossus Slayer/Planar Warrior:(Ranger 3): Most of the ranger subclasses get a few extra damage die. Decent.
Divine Fury(Zealot 3): A free d6 is always welcome.
There are also a lot of 'smite spells' as well as things like zephyr strike, which will buy you a few d8s and d6s here and there, but they're all very similar (not great) for our purposes so I won't call them out individually.
Are GWM/Sharpshooter bad for a crit-fishing build?
Well, no. If you roll a crit, you're going to hit pretty much regardless of the -5 or not. In fact, because both critfishing and GWM/SS require you to find advantage, these abilities work pretty well with each other. GWM in particular give an extra attack on each crit, which is insane. for builds like this.
Builds:
Feats: Sharpshooter.
Not a crit-fisher, not really, but it has absurd crit damage, and a decent way to get crits. You can hit people from an absurd distance, you're invisible in the dark, you have expertise in stealth, and if you surprise an enemy, you get an automatic critical and deal silly damage. Death Strike lets you double damage against a target.
crit chance per attack:100% (while attacking a surprised target. Otherwise 10%)
Crit Damage:(2d8 (longbow) + 5(DEX) + 18d6(sneak attack) + 4d6(Ambush) + 2d8(dread ambusher) + 2d6(hunter's mark) + 10(SS)) * 2 = 228.
Is it practical? Sorta. You're probably better off going for two more levels in gloom stalker though. Few games make it to tier 4.
resources needed for listed damage? 1 first-level spell, surprise.
Feats:Orc Fury, Savage attacker, GWM.
Lays down fat crits. I know I said earlier that overkill doesn't exist, but in all seriousness it's a problem for this poor guy. You go up to bash a goblin and then you accidentally deal a hundred damage. Good news is, he doesn't really need to expend resources to hurt things. Even better news is that unlike the other two builds listed here, he can get 2-3 attacks off a turn, so he's much more consistent and his DPR is much higher than the numbers suggest.
Crit Chance Per Attack: 19%
Crit Damaget: 2d12 (greataxe) + 5(STR) + 3d12(Brutal Critical) + 1d12 (Savage Attacks) + 2d12(Orcish Fury) + 2d6 + 10(Divine Fury) + 5.5 (Savage Attacker) + 5.3 (GWF) + 4(rage damage) + 10 (GWM)= 99
Is it practical? Yup! You can easily dump Savage Attacker from this build, but otherwise this is a very tough, effective build. Playing a zealot isn't really required here, any barbarian will do.
resources needed for listed damage? 1 short rest ability (orcish fury) and 1 usage of rage.
Feats: Elven Accuracy, Magic initiate:Wizard(find familiar)
Ivocations:Eldritch Smite, Thirsting Blade, lifedrinker
You too can live a breaking benjamin song! Hexblade's curse expands your range, your familiar gives you one source of advantage and leaves your concentration free. Or you can just skip the fishing and quicken hold person before running in. Your call.
Crit Chance per Attack: 27%
Crit Damage: 2d8(longsword) +5(CHA) + 10d8 (smite)+ 10d8 (eldritch smite) + 2 (dueling) +8d8 (GFB/BB) = 142
Is it practical? Sure. However, bursts like the one shown above consume too many resources, so you're probably better off with a more stable sorcadin build. Note that twinning and quickening the blade attack cantrips is a really good way to fish for crits, since you can get up to four cantrips in a turn (not targeted at one person, however.) Note that you're also kinda low on HP.
resources needed for listed damage? Hexblade's curse(1/sr), 2 4th level spells.