Does somebody already have a good build for the oni?

It kinda depends on what you're going for, but since his major strengths play around injuring survivors, perks that make healing slower, discourage it, or let's you take advantage of it are probably the best ones for him.

Sloppy Butcher is probably the ideal pick, Thanatophobia is kinda weak and his TR is too big to really make good use of Nurse's Calling like a Michael or Ghostface would. Infectious Fright would also be really good, since survivors will spend most of their times injured and you have an insta-down ability with him that let's you snowball extremely fast and put immense pressure on survivors.

Otherwise, information perks that let you see auras or find survivors quickly around the map are also good picks. BBQ and Chili sounds good but you lose your power when you pick-up survivors while it's activated, so it's not necessarily the best choice. You also make a lot of crows run away on your own during Demon Rush so Spies in the Shadows might not be too great. I'm All Ears would be optimal considering how quick he can end a chase, but be weary of the hefty cooldown.

And something to prevent progress like Pop Goes The Weasel, since he's able to quickly travel around the map like Billy but with no cooldown.

Ruin or Corrupt Intervention are good too since Oni kinda struggles during the early game.

Ultimately it's up to you to pick what would suit you best, since your own playstyle determines a lot of what you should be aiming towards, just be sure to use whatever compliments Oni's abilities and strengths the most.

@inthelive

The Killer hasn't been released yet, so it's unlikely. But I can provide some advice if you're still interested... despite the question being answered already.

For one, The Oni benefits greatly from knowing where other Survivors are during his "Yamaokas Wrath" ability. During this, if you pair a perk called "Infectious Fright" with his build, than you can actually down several Survivors that's close by IF you're skilled enough.

The perk Infectious Fright allows The Oni to gain a noise and visual notification of any Survivors nearby in a set radius. During his powers ability, he can down one Survivor and gain this notification after doing so. After that, you can decide to continue the downing chain or just pick up the Survivor you just downed.

If you continue the chain, you could start a very effective "Snow ball effect" and gain a lot of map pressure and hooks on Survivors that you downed.

Another thing The Oni benefits from is a perk called "Save The Best For Last." Like many Killers, this perk reduces the "weapon cooldown" after successfully hitting a Survivor with your basic M1. As such, you can actually combine this perk with your basic M1 attacks to gain fast downs and power up your Yamaoka's Wrath EVEN FASTER!

The perk actually does increase the animations for sucking up a Survivors blood (When they're healthy) and the Yamaoka's Wrath "Club hit cooldown"

So keep in mind that this perk does work pretty well on The Oni because of these reasons... With this perk you can maximize your downing potential with enough tokens.

an important tip

If you pair Save The Best For Last with the perk "Nemesis" you can actually attack Survivors you normally wouldn't be able to and still gain tokens for STBFL. Nemesis is quite a unique and cool perk, it opens up a lot of obsession build potential and can actually benefit The Oni GREATLY!

For context, Nemesis changes whoever your obsession is when you're blinded or stunned by them. That means using the perk Head-On on The Oni, stunning them with a pallet, or blinding them with a flashlight will turn that Survivor into your obsession.

While it is quite "counter intuitive" with a perk like STBFL, the new obsession isn't actually going to be marked as the obsession with regular hits... so in theory, if you're good enough you can actually avoid the stuns and still gain tokens from those Survivors.

And, if they stun you while other Survivors are nearby, you can break off that chase and gain new tokens from the previous obsessions.

but

Admittedly, this won't work 100% of the time. So, it's important to know that STBFL isn't the best perk to pair with Nemesis UNLESS you know how to manipulate the perk with STBFL.

It's better to pair Nemesis with something like Remember ME! to gain a lot more tokens on the Exit Gates, or using this perk with Furtive Chase can actually benefit The Oni a lot more than STBFL.

Furtive chase gains a token each time your obsession is hooked... and since Nemesis changes the obsession each time you're stunned, you can actually gain the max tokens on Furtive Chase REALLY QUICKLY. Knowing this, you can have a Tier lll Furtive Chase grant you -16 Terror Radius to Onis base 32 Terror Radius... This is huge for The Oni, especially since Nemesis also grants The Oni the oblivious status effect on that new obsession (For a set amount of seconds.)

basically, this is what the build would look like

It would be something like Pop Goes The Weasel, Nemesis, Save The Best For Last/Furtive Chase, and Remember ME!

Granting The Oni a pretty good obsession build...

For a basic build you'll use something like Ruin, Pop Goes the Weasel, Save The Best For Last, and Enduring. or you can go the Billy route and switch STBFL with Spirit Fury. Granting him a free down because of this perk combo and how his power works.

WAYYYY too long didn't read at all (TL;DR)

Try this unique perk build that works well with The Oni. Save The Best For Last cuts a lot of his animations down with enough tokens, granting him faster downs and quicker chases.

Remember ME! paired with Nemesis is a decent combo, Nemesis changes who the obsession is whenever you're stunned or blinded by that Survivor. This will help you easily gain enough tokens for the End game with Remember ME! and give you a bonus status effect on Survivors when they're the new obsession.

When they're chosen as the new obsession through a blind or stun, they'll be given the oblivious status effect for 40 seconds+ (depends on the tier) and their aura is revealed to your for 4 seconds (also depends on what tier the perk is.)

Now, STBFL isn't the greatest with Nemesis, so you'll want to most likely toss that perk out and switch it with Furtive Chase. If you have Tier lll Furtive Chase with a full 4 stack of tokens, than The Onis Terror Radius is reduced to 16 instead of his base 32. Combine that with Nemesis's side oblivious effect and The Oni is a pocket stealth Killer!

And use Pop Goes the Weasel to reduce generator progress... or Ruin... you don't really need Ruin on The Oni but that's up to you.

Read the "Basically, this is what the build would look like" above for other basic builds, but this is one of his more unique builds to try out...