i genuinely dont understand vaal hazak

[Tyrannus]

i dont ♥♥♥♥♥♥♥ get it. sometimes his mist damages me, sometimes it doesnt. sometimes his mist reduces my max HP, sometimes it doesnt. Somtimes, im not even in the mist at all, and Im taking damage. Sometimes, im not in the mist at all, and my health miximum is reduced. It like literal RNG as to what happens and i dont understand this guy. are the visuals bugged? does the mist have a much bigger hitbox than the visuals suggest? i had this problem fighting regular vaal hazak, i just got lucky and hack 'n slashed through it. now im fighting blackveil vaal hazak and i still dont ♥♥♥♥♥♥♥ understand this ♥♥♥♥. the mechanics make no sense. the mist is bugged or something

[Smaugi]

Take miasma resist and forget it exists.
Still deals damage but all you have to do is look at your hp

[Seamus]

Miasma causes a buildup that causes the max hp reduction effect when it gets high enough any time you're in a cloud or hit by most of vaal's attacks.

You'll need miasma resist decorations or just to carry nulberries.

[CookedMeat]

1. As Seamus already stated clearly, miasma works like any other status like para/sleep, where the (hp reduction) effect starts as soon as it accumulates up to a certain threshold. IIRC, not only Val can cause miasma effect, some infected monsters in Rotten Vale are also capable of this build up.
2. There are naturally occurred miasma in Rotten Vale that will constantly drain health, but extremely slowly. Val Hazak releases a stronger miasma fog wherever it goes while in combat, which drains life much faster. The visual is a bit hard to tell though.
3. Blackveil Val is even more frustrating, as it leaves spore stains on ground that does AoT damage, and are also capable of building up miasma status.
4. Just use miasma resist, the fight will be trivialized instantly. Val is a super slow monster and has very forgiving hit box most of the time.

[River Victor]

All around its body, Vaal generates dmg ticks. It has two effects: constant HP decrease and miasma build up. The first is obvious.

As for the second, the build up is not visible to you. Miasma build up will decrease your health by half once it hits the threshold. You can avoid all the big hits, but eventually, this miasma build up will accumulate and half your health.

All attacks have miasma build up value. Each hit breath attack will deal a chunk of it. So depending on how long you've been in the miasma and how often you get hit, chances are that the next big hit will half your health. It doesn't always happen if you're hit early in.

You can negate this halved-health effect by using:

Nullberries, Cleanser Booster (the blue smoke fount), Immunity Mantle. These three will remove the status effect, but you'll have to heal back up from that still. Immunity Mantle also prevents build up for as long as it lasts and prevents your health from being halved if you use it premptively.

Or you can use Miasma Jewels x3, or Miasma Jewel +3 x1, or Miasma Charm. The last three gives you Effluvia Resistance +3 which completely disable the build up. Nothing Vaal can do to you will half your health. Effluvia Res is the most convenient method.

However, NOTHING CAN STOP THE PASSIVE DAMAGE TICKS.

Blackveil Vaal also has its nova, which is kinda weird, but won't affect most melee players. It will fly up and spill chunks of noxious lumps and generate a donut-shaped AOE. The center is safe, and the meat of the donut drains your health like street walkers drain your wallet. This stack with its passive miasma dmg ticks, so it is very deadly if you're range and caught in it. It stays for a long time and sometimes Vaal will lure you to fight in it. This will kill you if you don't observe the ground for thick smoke.

[Tyrannus]

Originally posted by River Victor:

All around its body, Vaal generates dmg ticks. It has two effects: constant HP decrease and miasma build up. The first is obvious.

As for the second, the build up is not visible to you. Miasma build up will decrease your health by half once it hits the threshold. You can avoid all the big hits, but eventually, this miasma build up will accumulate and half your health.

All attacks have miasma build up value. Each hit breath attack will deal a chunk of it. So depending on how long you've been in the miasma and how often you get hit, chances are that the next big hit will half your health. It doesn't always happen if you're hit early in.

You can negate this halved-health effect by using:

Nullberries, Cleanser Booster (the blue smoke fount), Immunity Mantle. These three will remove the status effect, but you'll have to heal back up from that still. Immunity Mantle also prevents build up for as long as it lasts and prevents your health from being halved if you use it premptively.

Or you can use Miasma Jewels x3, or Miasma Jewel +3 x1, or Miasma Charm. The last three gives you Effluvia Resistance +3 which completely disable the build up. Nothing Vaal can do to you will half your health. Effluvia Res is the most convenient method.

However, NOTHING CAN STOP THE PASSIVE DAMAGE TICKS.

Blackveil Vaal also has its nova, which is kinda weird, but won't affect most melee players. It will fly up and spill chunks of noxious lumps and generate a donut-shaped AOE. The center is safe, and the meat of the donut drains your health like street walkers drain your wallet. This stack with its passive miasma dmg ticks, so it is very deadly if you're range and caught in it. It stays for a long time and sometimes Vaal will lure you to fight in it. This will kill you if you don't observe the ground for thick smoke.

OK I think i need effluvia resistance then. itll save me a lot of time healing and using nullberries.

[Seamus]

Originally posted by Rinoceronte:

OK I think i need effluvia resistance then. itll save me a lot of time healing and using nullberries.

Just note there's a difference between effluvia resistance and effluvial expert. Expert is mostly worthless and does essentially nothing for the vaal fight.

[sturmishes]

personaly i always slot in 3 miasma resist jewls and ends up a piece of cake, thought his beam stil hurts and his acidic aura when he has it, but no mmore eff, issues. Thoigh slotting in 3 jewls, makes it the easiest Elder Dragon ever.

[Hammer Of Evil]

you can also get effluvia status by being injected with a girros that has the 'effluvia swirl' - something to note if vaal is nearby doing his effluvial drain attack =p

and if you were looking to reduce damage from his beam attack, you'd need to make sure your water resistance isn't at -15 =)

everyone else covered it all, so its up to you from there.

[Schrader]

Get 3 miasma resist jewels and he turns into a slightly harder Laviasoth

[turbogum]

There's also one more thing that no one here seemingly mentioned that you possibly didn't notice:

There are pools of bright blue acid all over the lower areas in Rotten Vale, you might be stepping into them accidentally while fighting him and they drain your health rapidly.

Other than that, yeah, both Effluvial Expert and Effluvia Resistance are useful, you can also use Immunity Mantle or Cleanser Boosters. Hunting Horn can also negate all ailments.

[Cid]

either you bring Immunity Mantle or spam NullBerry if you are low on miasma resist jewel