Cohort of Chaos Feat

I'm both a chronic lover of frequently unloved abilities in games and also have great fun with chaotic rules. Needless to say the Cohort of Chaos feat is very attractive to me. I'm rather surprised its as hated as it is. Sure it needs some specific builds, but actually not too specific. But I'll come back to that.

The Cohort of Chaos feat comes from Planescape and requires both 4th level and Scion of the Outer Planes. Perhaps that right there is why it seems to be unloved as too many DMs simply don't allow it. But provided your DM is okay with it, let's see what it can do.

It's a half-feat allowing you to boost any ability score by 1 making it very easy to slot into many preexisting builds. The other half (called flares) gets triggered on an attack roll or saving throw of 1 or 20. Each flare lasts until the end of your NEXT turn and only one flare can be active at once. Once triggered, you get one of four random effects.

• Battle Furry gives a creature you can see advantage on attack rolls at the cost of disadvantage on ability checks.
• Disruption Field is a range 5 AOE d8 damage roll with no Saving Throw which happens at start of turn or entering the area.
• Unbound is a teleportation effect based on your movement value.
• Wailing Winds gives a 15 ft radius sphere around you where everyone, including you, gets disadvantage on Wisdom saves.

So lets start with who wants this. As taking this assumes you want it to trigger as often as possible, any character who makes lots of attack rolls (of any sort) will trigger it more often getting more use out of it. Next, two of the effects have relatively shorts range implying the character should be comfortable at melee range (but doesn't necessarily need to be swinging a sword themself). Finally, two traits have negatives which you probably want to build around.

Let's talk first about triggering. I'm going to focus on attack rolls, as if you are doing lots of your own saving throws things probably aren't going well for you and this feat isn't going to bail you out. So on attack, it triggers 10% of the time per attack. Oddly enough, due to the way Advantage is worded, you MUST take the higher roll so Advantage actually gets the feat to trigger slightly less frequently, but close enough to 10% to make it basically equal. Elvish Accuracy would get you a net positive on triggers. So most of the time it will trigger once every 10 attacks on average. But as 10 attacks only gives you a roughly 65% chance of triggering it over a specific 10 attacks you can't rely on it for any particular battle. But it does tell us it should trigger roughly once per combat assuming three attacks per round and three rounds per combat. Most of the effects works best the earlier they are triggered so having a high initiative makes it more likely to use it at a useful time.

So basically you get one of the four effects roughly once per combat. This is roughly comparable to effects you can use a number of times equal to a trait or proficiency bonus once per long rest, or two uses per short rest. Not bad, but lets look at the effects to see if they are worth it.

Battle Furry is the best looking from a combat munchkin point of view. I will often gladly take Advantage for the rest of this turn AND all of next turn, including any attacks of opportunity in between, in exchange for disadvantage on ability rolls. The two most important ability rolls in combat are probably grappling rolls and hide/perception rolls (whichever side you are one). Disadvantage on ability rolls is roughly equivalent to a minus 3 or so on the roll on average. Therefore, with sufficient bonuses on the rolls you are most worried about failing you can probably be okay with it. However, you don't have to use Battle Furry on yourself! You can put it on your enemy to give them disadvantage on ability rolls.

Why would you do this? We already know melee characters are the most likely to want this feat so putting disadvantage on your opponents grapple rolls can be very useful. Particularly if you can negate their advantage to attacks in some way. Shoving first would give them disadvantage on melee attacks negating advantage. Second, a raging barbarian might already be giving them advantage against themself making more advantage moot. Third, a successful grapple by a character with reach might make it impossible for the enemy to make any attack at all (if they don't have a ranged attack or reach themself).

Disruption Field is pretty strait forward. You want to be next to the enemy and not next to your friends. Anyone next to you takes d8 force damage with no save. Do I really need to delve into this one more?

Unbound is probably has the most skew on how useful it is. If it's a relatively simply combat with melee folks closing to slug it out, Unbound will probably only matter if you get in over your head and need to teleport out to avoid attacks of opportunity. Unfortunately as an escape mechanism it is obviously not dependable. However, in slightly more complicated combats with your character wants to close with the main bad guy or back row casters and needs to jump over the melee front line, or to get over obstacles such as pits or cliffs, then Unbound might be exactly what you need. Or it may trigger and absolutely nothing of value may come of it.

Wailing Winds is the one you most need to prepare for. In some combats the negative will be meaningless if the enemy doesn't force any WIS saves on you. In other combats, it could be crippling. Therefore, you need either a high WIS save (however you wish to get it) or something like the Kalashtar lineage which gives you advantage on WIS saves. However, once that is accomplished, you yourself don't need to be able to take advantage so long as you have a Save or Suck caster in the party who has spells like Hold Person or Command.

So to build around it, you could always simply add it to many pre-existing Crossbow Master or Polearm Master builds once you correct for the WIS saves.

Of particular interest would be a Polearm Master Path of the Giant Barbarian. Polearm Master gives you another way to use your reaction for another attack and Path of the Giant gives you reach when you rage allowing you to go the grappling route.

An Plasmoid Astral Self Monk also gives you reach for grappling (using your WIS score) and the Monk as pretty good saves already for WIS.

A caster like the Artillerist Artificer can use Scorching Ray for three attacks on a turn followed by a bonus ballista attack. Their armor makes them less shy about getting close and the Gunner Feat could help (any ranged character) survive up close in Melee.

Warlocks have Eldritch Blast of course. My favorite melee warlock is a STR based Genie Warlock who uses Pact of the Blade to get a double scimitar and he always will rub it in any Elf's face.

And so on. It's not game defining but with a little work you can add a sprinkle of chaos to your character.