Tanking Mechanics

[Kane0]

A bit of a recurring topic is how 5e lacks tanking mechanics, or specific kinds anyways. The sort of thing that influences the opposition's movement and targeting choices rather than simply increasing your own defences. So I figured I may as well make a quick list of what's currently available and where you can get it, plus open up the floor for ideas on how these mechanics can be expanded on with houserules, homebrew and other material.

*Note: Of course everyone has their own particular definition of a tank and what qualifies as tanking, so in this case my rule of thumb is 'closing with or drawing in the enemy and then preventing them from escaping or attacking others', which does not take into account your own capacity to take or avoid damage. I won't be counting things that drive creatures away, cut them off or stop them from acting entirely such as pushes, frightening/turning, Wall of X or stun/paralysis effects as I categorize those under 'debuff/control' instead, same with providing Temp HP or bonus AC to allies going into the 'buff' category. I'm aware that one could easily make the reverse argument with things like Difficult Terrain and 'thorn' damage and so I acknowledge the line is a blurry one.

'Encouragement'
Opportunity Attacks (PHB base rule)
Extra Opportunity Attacks (DMG Mark variant rule, Vigilant Defender [Cavalier Fighter 18])
Ignore Disengage + reduce speed to 0 + hit creature attacking other target (Sentinel feat)
Chase enemies (Relentless Avenger [Vengeance Paladin 7], Relentless Hex Invocation)
Damage for moving enemies (Booming Blade, Spike Growth)
Deny enemy reactions (Open Hand Monk 3, Shocking Grasp)
Shoves/Grapples (PHB base rule, Shield Master/Tavern Brawler/Telekinetic feats, Grappling Strike maneuver)
Knocking Prone (Raging Storm: Sea [Storm Barbarian 14], Totemic Attunement [Totem Barbarian 14], Tales from Beyond [Spirits Bard 3, 1/12 chance], Ferocious Charger [Cavalier Fighter 15], Telekinetic Thrust [Psi Fighter 7], Trip Attack maneuver, Open Hand Monk 3, Water Whip Discipline, Mighty Swarm [Swarm Ranger 11])
Advantage on Opportunity Attack (DMG Mark variant rule, Unwavering Mark [Cavalier Fighter 3])
Advantage to hit you (Reckless attack )
Disadvantage to hit other than you (Thunder Gauntlets [Armorer Artificer 3], Ancestral Protectors [Ancestral Barbarian 3], Totemic Attunement: Bear [Totem Barbarian 14], Improved Warding Flare [Light Cleric 6], Unwavering Mark [Cavalier Fighter 3], Goading Attack maneuver, Compelled Duel)
Pull enemy towards you (Perfected Armor [Armorer Artificer 15], Water Whip Discipline, Grasp of Hadar Invocation, Gravity Well [Gravity Wizard 6], Lightning Lure, Pulse Wave, Grasping Vine, Gravity Sinkhole)
Reduce target speed (Lance of Lethargy Invocation, Slasher feat, Ray of Frost)
Reduce target speed to 0 (Raging Storm: Tundra [Storm Barbarian 14], Hold the Line [Cavalier Fighter 10], Stone Rune [Rune Fighter 3], Nature's Wrath [Ancient Paladin 3], Aura of Conquest [Conquest Paladin 7], Event Horizon [Gravity Wizard 14], Ensnaring Strike, Watery Sphere, Bigby's Hand)
Cannot move beyond 30' from you (Champion Challenge [Crown Paladin 3], Compelled Duel)
Generate Difficult Terrain (Wild Surge [Wild Barbarian 3, 1/8 chance], Spike Growth, Warding Wind, Plant Growth, Sleet Storm, Spirit Guardians, Maelstrom)
Generate Cover (Fortified Position [Artillerist Artificer 15], Twilight Shroud [Twilight Cleric 17], Bulwark of Force [Psi Fighter 15])

[B]Prevention/Reduction
Impose Disadvantage against ally (Deflect Attack , Protection Fighting Style, Runic Shield [Rune Fighter 7])
Apply Resistance to ally (Ancestral Protectors [Ancestral Barbarian 3], Dampen Elements [Nature Cleric 6], Expansive Bond [Peace Cleric 17], Aura of Warding [Ancients Paladin 7])
Reduce damage taken by ally (Spirit Shield [Ancestral Barbarian 6], Interception Fighting Style, Protective Field [Psi Fighter 3], Bastion of Law [Clockwork Sorcerer 6], Guardian Coil [Fathomless Warlock 6], Projected Ward [Abjurer Wizard 6])
Take damage in an ally's place (Protective Bond [Peace Cleric 6], Shadow Martyr [Echo Fighter 10], Cloud Rune [Rune Fighter 3], Divine Allegiance [Crown Paladin 7], Aura of the Guardian [Redemption Paladin 7])
Reduce enemy attack/damage roll (Cutting Words [Lore Bard 3], Cosmic Omen: Woe [Stars Druid 6], Bend Luck [Wild Sorcerer 6], Chronal Shift [Chrono Wizard 2], Portent [Diviner Wizard 2], [I]Silvery Barbs)

Adding more bodies to the field
Homunculus (Artificer 2)
Turret (Artillerist Artificer 3)
Iron Defender (Battlesmith Artificer 3)
Dancing Item (Creation Bard 6)
Wild Companion (Druid 2)
Wildshape (Moon Druid 2)
Fungal Infestation (Spore Druid 6)
Wildfire Spirit (Wildfire Druid 3)
Manifest Echo (Echo Fighter 3)
Beast/Primal Companion (Beastmaster Ranger 3)
Drake Companion (Drakewarden Ranger 3)
Hound of Ill Omen (Shadow Sorcerer 6)
Pact of the Chain (Warlock 3 Pact Boon)
Accursed Specter (Hexblade Warlock 6)
Summon X/Conjure X, Animate X
Dance Macabre/Create Undead

Plus as a bonus to get started with the custom content ideas, a few that i've come up with:
- Polearm fighting style: When wielding a reach weapon enemies treat the area within your reach as difficult terrain
- Alternate Turret for Artillerist Artificer that drags creatures in an area towards it
- A feat or feature that causes enemies you knock prone to be unable to take reactions until the start of your next turn
- A 5e version of the Lightning Reflexes feat that provides additional reactions
- Rogues being able to trade d6's of Sneak Attack damage in order to inflict rider effects like knocking prone, denying reactions, etc
- Barbarians being able to expend uses of Rage for alternative effects, like for example a concentrationless Warding Wind for Storm Heralds (which could also trigger their aura as if they entered regular rage)
- Minor improvements to existing options like Protection fighting style (after the roll rather than before),
- A paladin or ranger subclass that gets bonus AoE, zone-style spells (Spike Growth, Sleet Storm, etc) and can exclude themselves from the effects of those spells

Keen to hear everyone's thoughts!

[Greywander]

In addition to noting class and level, you might also name the specific ability that allows you to do these things. For example, off the top of my head I'm not sure what a warlock gets at 7th level that helps with chasing enemies.


*Note: Of course everyone has their own particular definition of a tank and what qualifies as tanking, so in this case my rule of thumb is 'closing with or drawing in the enemy and then preventing them from escaping or attacking others', which does not take into account your own capacity to take or avoid the resulting damage. I won't be counting things that drive creatures away, cut them off of stop them from acting entirely such as pushes, frightening/turning, Wall of X or Stun/Hold effects as I categorize those under 'debuff/control' instead, same with providing Temp HP or bonus AC to allies in the 'buff' category. I'm aware that one could easily make the reverse argument with things like Difficult Terrain and 'thorn' damage and so I acknowledge the line is a blurry one.
I think this is sensible for what you're wanting to discuss. However, I will say that this isn't necessarily the best way to protect your party, and certainly not the only way. We can talk about roles like control, support, buff, debuff, etc., but at the end of the day, there are only two major categories: offense and defense. If we were to talk about the entirety of defensive strategies, then we'd be here all day, just know that there are a lot of different ways to keep the party alive.

The only thing I'll say for now on the broader topic of defense is that you can create a very solid core by take an Artillerist artifier to provide temp HP (and later, +2 to AC and DEX saves) every round, a paladin to buff the party's saves, and a Life cleric to top off any actual damage that gets through, and everyone should be in at least medium armor and a shield. Shield Master can help negate AoE damage since you'll need to stay in a tight formation for the temp HP and save buff. Peace cleric can further augment your defense, but at that point you probably have all the defense you need and should be looking at offense. Fireball can be a defensive spell if it means taking 30 fewer attacks next round and every round thereafter.


Deny enemy reactions (Open Hand Monk 3)
I know you mention it under Spells, but it might be worth mentioning Shocking Grasp here.

You could also have "reaction baiting", where you do something to provoke an enemy to use their reaction. For example, baiting on opportunity attack from an enemy that you know has Counterspell so your own casters can cast without fear of being Counterspelled. Bonus points if you have a way to get them to use their reaction, then deny whatever the reaction was. Not sure that there's much here aside from provoking an OA, though.


Apply Resistance to ally (Ancestral Barbarian 3, Nature Cleric 6, Peace Cleric 17)
Ancients paladin.

The paladin's Aura of Protection and various other status immunity auras might be worth mentioning. I know you said you weren't going to cover AC buffs (and I assume that extends to saves), but if it can turn a failed save into a pass or prevent a PC from being dominated and forced to attack the party, then those are probably at least worth noting.


Adding more bodies to the field
While this does apply to any kind of summon spell, I feel like Conjure Animals might merit special mention, just due to how potent it is. 8 of any number of animals adds a lot of bodies to the field, and even if they go down in one hit, that's still 8 attacks that the party isn't taking. There are also large sized options like cows, so you can use this like a Wall spell. Which, fair enough, you said you weren't going to cover (although I'm not sure why adding bodies is fine but walls aren't; honestly, some of the things you've decided to include or exclude seem kind of arbitrary).


Echo (Echo Fighter 3)
The echo is actually really good. You can make OAs against enemies who try to move away from it, you can switch places with it, giving you a rather long range teleport, you can attack from the echo's space. It really is good for area control, almost like having a second martial on the field. Plus, the echo is an object, so there's very little except a direct attack that can even hurt it; almost all AoE doesn't affect objects. And then if it does die, you just resummon it as a BA; there's no resource cost or limit except you can only have one at a time.

I think the echo shows how tricky of a topic this can be to discuss. The echo isn't just an extra body, but it's hard to really convey the value of the echo and what it can do without launching into an in-depth discussion on just that one feature of that one subclass, and you don't have the time to dedicate that much attention to everything you've listed in the OP.


Spells
Booming Blade, Lightning Lure, Ray of Frost, Shocking Grasp, Compelled Duel, Ensnaring Strike, Silvery Barbs, Spike Growth, Summon X, Conjure X, Warding Wind, Animate Dead, Plant Growth, Pulse Wave, Sleet Storm, Spirit Guardians, Grasping Vine, Gravity Sinkhole, Watery Sphere, Animate Objects, Bigby's Hand, Danse Macabre, Maelstrom, Create Undead
Maybe move these up to the specific thing they do, e.g. Shocking Grasp to denying reactions?


- A 5e version of the Lightning Reflexes feat that provides additional reactions
I wrote up something like this a while back. Not only did it give you a second reaction, but it also gave you a reaction to gain +2 AC against one attack or +4 to a DEX save, like a more limited version of the War wizard's Arcane Deflection.


- Minor improvements to existing options like Protection fighting style (after the roll rather than before)
I think I've seen it proposed that the Protection style be given to everyone by default. I think I suggested that myself in another thread recently, but with the caveat that two-handing and TWF needed a similar buff. A replacement fighting style for Protection should be one that provides cover to those behind you (possibly as a reaction to an AoE, or as an action or bonus action on your turn), giving full cover to anyone directly behind you, 3/4 cover to those mostly behind you, and half cover to anyone in a cone shape behind you. This feels like it should be limited use, though... but maybe positioning would be a sufficient limitation.

[strangebloke]

Great list, really appreciate it.

I would add tavern brawler under the grappling point, as its really efficient in the same way shield master is, especially as its a half feat. The main drawback is needing to make an unarmed strike, but with tavern brawler your unarmed attacks deal 1d4 so its only a loss of 1 or 2 damage compared to a shortsword or longsword, and ofc the unarmed style from fighter is insanely good here. A BA grapple on a half feat is a very good deal. The Grappling Strike maneuver from BM lets you do the same thing with fewer preconditions (though you also need to spend a resource to do it)

[Kane0]

Certainly, i've made some adjustments as mentioned and will work on specifying the ability names.


However, I will say that this isn't necessarily the best way to protect your party, and certainly not the only way. We can talk about roles like control, support, buff, debuff, etc., but at the end of the day, there are only two major categories: offense and defense. If we were to talk about the entirety of defensive strategies, then we'd be here all day, just know that there are a lot of different ways to keep the party alive.
-
Which, fair enough, you said you weren't going to cover (although I'm not sure why adding bodies is fine but walls aren't; honestly, some of the things you've decided to include or exclude seem kind of arbitrary).
-
I think the echo shows how tricky of a topic this can be to discuss. The echo isn't just an extra body, but it's hard to really convey the value of the echo and what it can do without launching into an in-depth discussion on just that one feature of that one subclass, and you don't have the time to dedicate that much attention to everything you've listed in the OP.

Yes I had to draw a line somewhere, otherwise things could get really abstract really quickly. I wasn't even sure if I wanted to go down the path of counting extra bodies honestly, since it largely comes down to 'more of the above, but expendable'.

Sidenote, an observation to make is that rangers, rogues and monks appear to be rather sparse on tanking options which probably makes sense given they aren't typically associated with drawing attention to themselves in a fight. Still, I think a guardian type ranger subclass would be cool, a lot of the basic tools are already available to them. Warden seems like a natural fit for the name.

And it's probably worth mentioning that I've been working on a Storm Herald rework with an eye towards making it an alternative to the Ancestral Guardian, the same way that fighters have multiple subclasses that allow them to tackle tanking in different ways.

[SociopathFriend]

So I tried looking through the list several times but I can't help but skim-

Do you have the good old fashioned, "Yell and taunt verbally as a free action" in there? Or is that not considered mechanical?

[Kane0]

Not there sorry, I limited this to class/subclass features, feats and spells. If there is a listed check somewhere with DC/effect/duration that isnt DM dependant then that would certainly qualify, however i'm not aware of any such Taunt checks.

Im not aware of any racial features off the top of my head but if there are any I would add those in.

[LudicSavant]

Sidenote, an observation to make is that rangers, rogues and monks appear to be rather sparse on tanking options which probably makes sense given they aren't typically associated with drawing attention to themselves in a fight.

Rogues can Sneak Attack on an OA, and Monks can stun on one (potentially canceling the rest of the enemy's turn). Mercy Monks can Hands of Harm on an OA (which is once per turn, not once per round) and thus inflict Disadvantage to hit with no save. Shadow Monks can often switch off features that would otherwise circumvent OAs or control (because they require either verbal components or sight). Astral Monks are grapplers. Open Hand can switch off reactions or punt people across the map so that they can't close with the target they want.

Rogues also are very Booming-Blade-friendly, just because they don't have Extra Attack. Between that and Sneak Attack, they can offer a fair dose of "encouragement."

[stoutstien]

Rogues can Sneak Attack on an OA, and Monks can stun on one (potentially canceling the rest of the enemy's turn). Mercy Monks can Hands of Harm on an OA (which is once per turn, not once per round) and thus inflict Disadvantage to hit with no save. Shadow Monks can often switch off features that would otherwise circumvent OAs or control (because they require either verbal components or sight). Astral Monks are grapplers. Open Hand can switch off reactions or punt people across the map so that they can't close with the target they want.

Rogues also are very Booming-Blade-friendly, just because they don't have Extra Attack. Between that and Sneak Attack, they can offer a fair dose of "encouragement."

Aye. Rogues are in the running for having the highest punishing/mitigation reaction(s) built right in and those can be further enhanced with feats/race. They are nearly as soft as people are lead to believe either so with a little planning they can have a moderately strong lockdown presence.

[Mostlymad]

Added more categories but I've only gone as far as the fighter class. I'll update this post with more feats/classes/races as I dig through them.
I split Grapple/Shove into Grapple and Move Enemy.
Also Added:
Sanctuary
Give Self +AC
Give Ally +AC
Move Ally

Perhaps format it this way to make easier to read? Also, perhaps we should do spells like: Shield[1] to spells to indicate level?

'Encouragement'
Opportunity Attacks (PHB base rule)
Extra Opportunity Attacks (DMG Mark variant rule, Vigilant Defender [Cavalier Fighter 18])
Ignore Disengage + reduce speed to 0 + hit creature attacking other target (Sentinel feat)
Chase enemies (Relentless Avenger [Vengeance Paladin 7], Relentless Hex Invocation)
Damage for moving enemies (Booming Blade[c], Spike Growth[1])
Deny enemy reactions (Open Hand Monk 3, Shocking Grasp[c])
Grapple (PHB base rule, Tavern Brawler, Grappling Strike maneuver)
Knocking Prone (Raging Storm: Sea [Storm Barbarian 14], Totemic Attunement [Totem Barbarian 14], Tales from Beyond [Spirits Bard 3, 1/12 chance], Ferocious Charger [Cavalier Fighter 15], Telekinetic Thrust [Psi Fighter 7], Trip Attack maneuver, Open Hand Technique [OH Monk 3], Water Whip Discipline, Mighty Swarm [Swarm Ranger 11])
Advantage on Opportunity Attack (DMG Mark variant rule, Unwavering Mark [Cavalier Fighter 3])
Advantage to hit you (Reckless attack )
Disadvantage to hit other than you (Thunder Gauntlets [Armorer Artificer 3], Ancestral Protectors [Ancestral Barbarian 3], Totemic Attunement: Bear [Totem Barbarian 14], Improved Warding Flare [Light Cleric 6], Unwavering Mark [Cavalier Fighter 3], Goading Attack maneuver, Compelled Duel[1])
Pull enemy towards you (Perfected Armor [Armorer Artificer 15], Water Whip Discipline, Grasp of Hadar Invocation, Gravity Well [Gravity Wizard 6], Lightning Lure[c], Pulse Wave[3], Grasping Vine[4], Gravity Sinkhole[4])
Reduce target speed (Lance of Lethargy Invocation, Slasher feat, Ray of Frost[c])
Reduce target speed to 0 (Raging Storm: Tundra [Storm Barbarian 14], Hold the Line [Cavalier Fighter 10], Stone Rune [Rune Fighter 3], Nature's Wrath [Ancient Paladin 3], Aura of Conquest [Conquest Paladin 7], Event Horizon [Gravity Wizard 14], Ensnaring Strike[1], Watery Sphere[4], Bigby's Hand[5])
Cannot move beyond 30' from you (Champion Challenge [Crown Paladin 3], Compelled Duel[1])
Generate Difficult Terrain (Wild Surge [Wild Barbarian 3, 1/8 chance], Spike Growth[1], Warding Wind[2], Plant Growth[3], Sleet Storm[3], Spirit Guardians[3], Maelstrom[5])
Generate Cover (Fortified Position [Artillerist Artificer 15], Twilight Shroud [Twilight Cleric 17], Bulwark of Force [Psi Fighter 15])
Move an Ally (Bait and Switch maneuver, Maneuvering Attack maneuver, Telekinetic Movement [Psi Fighter 3], Telekinetic feat)
Move an Enemy (PHB Action: Shove, Shield Master, Crusher Feat, Telekinetic Feat, )


Prevention/Reduction
Impose Disadvantage against Ally (Deflect Attack , Protection Fighting Style, Runic Shield [Rune Fighter 7])
[B]Apply Resistance to Ally (Ancestral Protectors [Ancestral Barbarian 3], Dampen Elements [Nature Cleric 6], Expansive Bond [Peace Cleric 17], Aura of Warding [Ancients Paladin 7])
Reduce Damage Taken by Ally (Spirit Shield [Ancestral Barbarian 6], Interception Fighting Style, Protective Field [Psi Fighter 3], Bastion of Law [Clockwork Sorcerer 6], Guardian Coil [Fathomless Warlock 6], Projected Ward [Abjurer Wizard 6])
Take Damage in an Ally's place (Protective Bond [Peace Cleric 6], Shadow Martyr [Echo Fighter 10], Cloud Rune [Rune Fighter 3], Divine Allegiance [Crown Paladin 7], Aura of the Guardian [Redemption Paladin 7])
Reduce enemy attack/damage roll (Cutting Words [Lore Bard 3], Cosmic Omen: Woe [Stars Druid 6], Bend Luck [Wild Sorcerer 6], Chronal Shift [Chrono Wizard 2], Portent [Diviner Wizard 2], [I]Silvery Barbs[c])
Give Self +AC (Bait and Switch maneuver, Evasive Footwork maneuver, Shield[1], Gift of the Metallic Dragon Feat, Warding Maneuver[Cavalier Fighter 7], Glorious Defense [Glory Paladin 15])
Give Ally +AC (Bait and Switch maneuver, Shield of Faith[1], Gift of the Metallic Dragon Feat, Warding Maneuver[Cavalier Fighter 7], Glorious Defense [Glory Paladin 15])
Sanctuary (Sanctuary[1], Tranquility [OH Monk 11])

Adding more bodies to the field
Homunculus (Artificer 2)
Turret (Artillerist Artificer 3)
Iron Defender (Battlesmith Artificer 3)
Dancing Item (Creation Bard 6)
Wild Companion (Druid 2)
Wildshape (Moon Druid 2)
Fungal Infestation (Spore Druid 6)
Wildfire Spirit (Wildfire Druid 3)
Manifest Echo (Echo Fighter 3)
Beast/Primal Companion (Beastmaster Ranger 3)
Drake Companion (Drakewarden Ranger 3)
Hound of Ill Omen (Shadow Sorcerer 6)
Pact of the Chain (Warlock 3 Pact Boon)
Accursed Specter (Hexblade Warlock 6)
Summon X[2-6]/Conjure X[3-7], Animate X[3,5]
Danse Macabre[5]/Create Undead[6]

[stoutstien]

I tend to break down mitigation into 5 categories. Used to be 4 but I split redirect and denial as redirect effects are no longer extremely rare.

Avoidance- AC, rerolls/disadvantage on enemy attacks, breaking line of sight/be hidden, out of range, type immunity, and anything else that flat out prevents the damage/effects from occurring.

Reduction- resistance and damage reduction mostly. Key point with reduction is it can effect concentration saves and increase the duration of spells/effects like AoA or arcane ward.

Redirect- forced target selection. Rare option but is one of the few true forms of making the enemies target who you want. In some cases it can even by another enemy.

Denial/reverse-ideally this is the gold standard of mitigation because it usually means the enemy loses its progress and resources/action. Counterspell and Tasha's mind whip are examples of denial.

Punishment- anything that just makes attacking or choosing an action a painful in some form. Booming blade, sentinel, and AOs are all punishment. This is usually the weakest form alone but it's also the easiest to combine with others and anyone can do it to some extent.

Something that gets misunderstood often is the way they relate to each other. Having high reduction doesn't make avoidance worth less in regards to how effective each is.

[Greywander]

I tend to break down mitigation into 5 categories. Used to be 4 but I split redirect and denial as redirect effects are no longer extremely rare.
Where would you put temp HP? Would it be a type of Reduction? I think damage to temp HP still counts toward concentration saves, and you said not doing that was a key point of Reduction.

Good list, by the way. I think it could be easily adapted to include saving throws, too. Save bonuses would be under Avoidance, and things like Evasion would probably be a combo of Avoidance and Reduction (since it either halves the damage or negates it entirely). Save for half damage effects do kind of blur the line between Avoidance and Reduction, since things like save bonuses that are normally Avoidance now only contribute to Reduction.


Something that gets misunderstood often is the way they relate to each other. Having high reduction doesn't make avoidance worth less in regards to how effective each is.
On the contrary, defensive abilities tend to be multiplicative. If you take only half damage, then you'll last twice as long. If you only get hit half as often, then you'll also last twice as long. If you do both, then you last four times as long. If you then get healed, that extra HP will also last four times as long. Not only that, but bonuses tend to stack in a non-linear way with themselves. For example, if an enemy has a 50% chance to hit you, then +1 AC decreases that to 45%, which is actually a 10% reduction in the number of hits you take. If an enemy has a 10% chance to hit you, then +1 AC reduces that to 5%, which is a 50% reduction in the number of hits taken.

In terms of AC, I define three threshholds that are defined as the amount needed to make a creature only hit you on a 20:

Mook Tier, which is equivalent to a 1st level PC with straight 14s, or to a goblin. +4 to hit means we need 24 AC to only be hit on a 20.
Boss Tier, which is equivalent to a 20th level PC with straight 20s. +11 to hit means we need 31 AC to only be hit on a 20.
God Tier, which is equivalent to a CR 30 monster with straight 30s. +19 to hit means we need 39 AC to only be hit on a 20.

Now here's the thing: God Tier AC is more than achievable. You do generally need armor +3 and a shield +3, and a few other AC boosting tricks, but there's a few different ways to get your AC that high, at least temporarily. And it doesn't need to be that high all the time, only when you're facing something with that large of a to hit bonus. Mook Tier AC is very easily accessible with just magic armor and/or a spell like Shield of Faith. A warforged in plate with a shield and the Defense style is already sitting at 22 AC, with no magic items or spells. Slap on Shield of Faith and you can wade into a group of goblins who each only have a 5% chance of hitting you. You can do this as early as 2nd level on a paladin, or a fighter 1/cleric 1, if you can afford plate armor.

Another interesting thing on the mutliplicativeness of defensive abilities: if an enemy only hits you on a 20, that's a 5% chance to hit. If you then give them disadvantage, e.g. with a Cloak of Displacement, that drops to a 1 in 400 chance to hit, or 0.25%. Imposing disadvantage gains value as your AC increases.

[stoutstien]

Where would you put temp HP? Would it be a type of Reduction? I think damage to temp HP still counts toward concentration saves, and you said not doing that was a key point of Reduction.

Good list, by the way. I think it could be easily adapted to include saving throws, too. Save bonuses would be under Avoidance, and things like Evasion would probably be a combo of Avoidance and Reduction (since it either halves the damage or negates it entirely). Save for half damage effects do kind of blur the line between Avoidance and Reduction, since things like save bonuses that are normally Avoidance now only contribute to Reduction.


On the contrary, defensive abilities tend to be multiplicative. If you take only half damage, then you'll last twice as long. If you only get hit half as often, then you'll also last twice as long. If you do both, then you last four times as long. If you then get healed, that extra HP will also last four times as long. Not only that, but bonuses tend to stack in a non-linear way with themselves. For example, if an enemy has a 50% chance to hit you, then +1 AC decreases that to 45%, which is actually a 10% reduction in the number of hits you take. If an enemy has a 10% chance to hit you, then +1 AC reduces that to 5%, which is a 50% reduction in the number of hits taken.

In terms of AC, I define three threshholds that are defined as the amount needed to make a creature only hit you on a 20:

Mook Tier, which is equivalent to a 1st level PC with straight 14s, or to a goblin. +4 to hit means we need 24 AC to only be hit on a 20.
Boss Tier, which is equivalent to a 20th level PC with straight 20s. +11 to hit means we need 31 AC to only be hit on a 20.
God Tier, which is equivalent to a CR 30 monster with straight 30s. +19 to hit means we need 39 AC to only be hit on a 20.

Now here's the thing: God Tier AC is more than achievable. You do generally need armor +3 and a shield +3, and a few other AC boosting tricks, but there's a few different ways to get your AC that high, at least temporarily. And it doesn't need to be that high all the time, only when you're facing something with that large of a to hit bonus. Mook Tier AC is very easily accessible with just magic armor and/or a spell like Shield of Faith. A warforged in plate with a shield and the Defense style is already sitting at 22 AC, with no magic items or spells. Slap on Shield of Faith and you can wade into a group of goblins who each only have a 5% chance of hitting you. You can do this as early as 2nd level on a paladin, or a fighter 1/cleric 1, if you can afford plate armor.

Another interesting thing on the mutliplicativeness of defensive abilities: if an enemy only hits you on a 20, that's a 5% chance to hit. If you then give them disadvantage, e.g. with a Cloak of Displacement, that drops to a 1 in 400 chance to hit, or 0.25%. Imposing disadvantage gains value as your AC increases.

THP falls under
Effective HP which is part of recovery which I view as the follow-up step after mitigation plays out. For most the differences aren't important but if you are trying to decide between something like a shield or a 2 handed weapon that proves THP when you hit ab enemy you have to break them apart to see the pros and cons on each.