With the huge nerf to cursed you need as much redundancy as possible to proc amp
Witch has something like 1/3 chance to use amp, seems WAY more frequent than her other curses or even attacks at range. Then when you hit 5/10/15/20 monsters at the same time with aura you've got 23/40/54/64% chance to cast amp on all of them every 2 seconds, and also 5% on her attacks, 5% per 1-3x blood star projectile, 5% per 4x charged bolts if lightning enchanted.
That said, the extra amp isn't worth having such a finnicky AI

feels awful tbh.
i played it in recent season and difference is day and night. skill breaking nerf. would be better if they just reduced dmg by 20%

So another point worth considering is just how valuable a stone skin physical immune monster can be now.
With the HP cap, bound demons can and do die to heralds, and still can be threatened by stuff like diablo lightning. That really wasn't the case when you could hit something stupid like 134k on a unique P8 TZ96 urdar or 423k on hephasto

But it has always been an option to make a demon that is simply immune to everything. Spectral hit is +20 fire/cold/light that won't apply if already 75%, but blood oath is ~77 fire/cold/light/poison and ~11% dr and engorge is another 5% dr
If a demon has 40%+ base dr and stone skin and 5/5/5/25+ base resists, it becomes immune to physical/fire/cold/light/poison. Still takes magic damage
Still can take damage from cursed / conviction mobs, but if its natively physical immune from 50% dr + stone skin, it gets the flag that makes it show up as physical immune when you hover over it and only reduces to 80% dr with amp (the few above 50% base dr can still be immune)
Same could be true for reducing fire damage, we'd prefer a natively 50% dr / fire immune mob so conviction also applies less.

And obviously, venom lord fits all these bills and applies amp. As long as its a unique venom lord with cursed + stone skin, you can roll for a holy aura. Ideally holy freeze, but if not, you could get it on your merc and not care much about the lost %ed.
Unfortunately it takes 20 bind demon to get infector of souls who could be easily rolled, so instead you'd have to farm for regular river of flame / chaos sanctuary.
Also the TZ sharding aspect wouldn't matter much. You could search during native TZ on those areas, but because the HP is capped in P8 and uniques don't inherit the TZ affix and its chance to hit / attack don't matter much when it sprays zero dps inferno, you could just skip all that.

Pit lords in river are 50 dr, 120/75/50/75 res, no magic. Venom lords in chaos are 50 dr, 130/75/50/75 res.
The difference in fire resist shouldn't matter because conviction from monsters shouldn't break the resist on its own either way
Its also level 15 vs 14 inferno but that doesn't matter much either, range/duration are identical and dps is still irrelevant. Level, damage, attack, defense, all identical. Slightly lower level if you use non-TZ from earlier parts of act 4, but they're also not worth checking in the first place, easy to teleport river/chaos.

Its not the easiest thing to get, you've only got a % chance for any stone skin + cursed venom lord to hit the right set of auras. But still probably one of the easiest unique monsters to spawn for stats because its a static map and static list of mobs in chaos unlike farming areas in A5 where they have random guest monsters. Once you get it, that venom lord should be 100% dr, 197/152/147/152% resist with phys/fire immunity. Against amp it becomes 80% dr, against conviction its still fire/poison immune but becomes 67% light, 62% cold. Cursed heralds could kill it, non-cursed can't, otherwise uber mephisto might be a danger but that's about it.

As a proof of concept on PTR version

I can kill p8 baal without engorge or town trip, keeping my bound demon at 0-5% hp, just resummon tainted so you can keep spamming blood boil. Its still not fast, the 20 tainted build has more dps, and there's no real reason to kill a p8 baal and its not efficient to farm statues let alone anything else
But the point being, a stone skin venom lord is actually unkillable in most scenarios. Only amp/decrep can even make it possible for monsters to kill him in normal play, though maybe conviction on herald burning souls could deal enough lightning
Since he's simply immune to physical/fire/cold/light/poison, he can sit in front of baal at 1 hp after you cast blood boil when he's at 5.001% hp and he still won't die



So now we've got a few forks in the blood boil build:

• Max tainted, don't bind at all, use 2t+1d or 3t, have much higher QoL but lose amp entirely and have lower mob DPS but much faster boss killing, with arguably higher kill speed on stomping uniques but lose all that advantage vs fire immunes where you just achieve ~parity
  
• Max bind, use an immortal venom lord for full amp damage procs and its will almost never die, but is hard to bind in the first place. You have maximum DPS blood boil for mob clearing, but not as much single target on bosses.
  
• Max bind, use a spearwoman and get a huge added source of physical DPS from demon attacks that boosts your single target / boss killing, not as much as tainted, but she very rarely procs amp on bosses which loses that purpose AND procs much less on mobs
  
• Max bind, use an immortal urdar for slightly less amp procs than spearwoman but good direct DPS and urdar can be fully immune, act 5 variant can even be immune to amp damage/decrep because it has 75% base dr, though it will only have 97% poison resist and have its regen disabled by poison, even possibly die though at 3% dps that won't happen much

maxing demon is bait if you have to engorge and are not using a super unique demon regardless so take the 5-10 extra points saved and run 1x tainted 1x big single target dmg demon 1x consumed tainted

you can get your tainted to be a 10frame 30k fb turret and use death mark in open areas to spread blood boil as your aoe

This post was edited by macohan on Apr 18 2026 12:30pm

Tainted with the normal 60% EIAS from mastery+engorge (its got ~150 duration so its not like you need to spam it) will hit at 22 FPA, because their 8 fpd / 3 af / 176 speed a1 animation is slowed by that speed parameter and has 11/7/6 frames with 0/60/67+ eias, so even adding sigil frenzy/fanat just speeds them from 22 fpa to 21 fpa. That's the big issue with tainted, blood boil hits 10+ yard radius at 9 fpa, while tainted hit some small radius (hard to know exact, but appears to be size of fireball or smaller, so 2-2.6) at 22 FPA. And blood boil can deal 60%+ of its maximum DPS to immune monsters because of all the piercing, while tainted can lose 90% of their DPS to immunes

A tainted build has some flexibility to use different demon count for different purposes without having to set up anything or bind a new demon
1 tainted + 1 defiler + 1 consume (or even 2 defilers + consume) gives the maximum blood boil AoE you'll get without binding an amp demon, you get the +20/-15 fire and defiler buff but only 1/3 of the tainted max
2 tainted + 1 defiler gives the most balance of dps as the defiler amplifies the tainted as well as blood boil, but you lose some aoe damage, so its better at killing unique packs but worse at clearing screens of trash
3 tainted gives the most boss killing, and you can just keep resummoning them without engorge against bosses because it doesn't matter the order you summon/unsummon demons if you're just going 3x tainted

On the balance I'd say the max tainted / no bound demon build probably works the best at the moment. Now I didn't post a clip of it vs baal, but it only saved "a few seconds" in that same kill comparison. It was clearly faster, but we're talking twice the speed rather than 10x the speed
i haven't tried anything fruity like a max prebuff tainted setup (+6 shield) that self-wields infinity and has an act 5 dual plague merc to proc lower resist, but that is also imaginable if you wanted to go ALL-in on tainted