Maybe find a better mutate target than bristling boar.

Maybe I can help you finding ideas with the mutate mechanic here's some list of rules that a lot of people don't really know yet

1. if there is a stack of mutated creatures and you play a copy creature onto them Clever Impersonator the copy gains all the ability of the entire stack
2. if a legendary creature is going to get mutated by a non legendary creature and the non legendary creature is on top it is not legendary the whole stack is't legendary
3. if a god is mutated into a mutated creature is on top and your devotion does not meet the requirements of making your god into the creature it becomes quite literally is nothing but a thing on the field but it stays there as proof of 110.4c (if a permanent somehow loses all its permanent types it remains on the battlefield. it's still a permanent)

So the way I would build the deck is find some good legendairy cards mutate them once and than copy them a bunch thus getting more triggers off of them

I hope these rules help you find the cards you want in your mutate deck!

Yeva, Nature's Herald and Vivien, Champion of the Wilds allow you to mutate at instant speed, with Kaseto, Orochi Archmage you can win with commander damage, Lazav, the Multifarious can do some nasty tricks with your graveyard, Glissa, the Traitor with trample is a real pain, Elusive Tormentor  ^Flip can be a solid target to mutate on. Hope this can help :)

I like the ability to flash out creatures, and lazav is nice to, since I’ve included Muldrotha as well for more graveyard recursion. Glissa is probably a no go since I don’t have many artifacts though.

And suggestions on cards to take out of my current list?

Infect. Do it. You know you wanna. Mutate a 6/6 onto Blighted Agent. Get some value out of that Ichor Rats and Viridian Corrupter. Eat a whole board with Flesh-Eater Imp. Dump your library into your graveyard, then make Corpse Cur and Otrimi bring both pieces back.

triproberts12 yeah I do want to include infect. In fact I had Blighted Agent in until I realized he was human and couldn’t be a target for mutate. Skittles is in my maybeboard because of how expensive he is, but thanks for more suggestions

Hey, infect seems powerful with Otrimi, but if you play casual then you will become the archenemy.

Don't underestimate Slippery Bogle and Gladecover Scout. Mutating a hexproof creature makes it safe to mutate not just the first time but other times after. Wizards helped the mutate mechanic by if the target creature you're mutating dies in response to the mutate then you still get the mutate creature on the battlefield, but it doesn't trigger "when this creature mutates" abilities. Instead it just ETB as another creature not mutated. With hexproof you don't have to worry about this.

Blossoming Defense and Vines of Vastwood are helpful spells for mutate because for one mana they can give any creature you want to mutate hexproof in response to removal. Crystal Shard can be repeatable bounce of an entire mutate pile back to your hand to then mutate again. Use this effect to change the creatures Otrimi is mutated to. To avoid Commander tax use Shard to bounce Otrimi back to your hand if it's stuck on the battlefield since it couldn't mutate.

Flying is a good ability to pair with Otrimi. Birds of Paradise and Maraleaf Pixie are mana dorks who fly. Needle Specter, Drana, Liberator of Malakir, Vampire Nighthawk give Otrimi good abilities. Specter has a busted combat damage trigger when it has 6 or more power. Drana can put a counter on the mutated creature and all other attacking creatures. Nighthawk mutated with Otrimi makes a 6/6 flying, trample, lifelink, deathtouch threat.

Jarad's Orders can tutor for a creature put it into your hand and tutor for a creature with mutate and put it into your graveyard to then recur it with Otrimi. Mask of Memory can be repeatable draw and discard and one mana to equip is nice.

Pernicious Deed can be powerful with Otrimi. If Otrimi is the top creature of the mutate pile then the pile has a CMC of 6. Sac Deed for less than six to hopefully destroy a lot of your opponents cards and not your mutate pile. All of the creatures on the bottom of the top creature don't count as creature cards on the battlefield. The only creature of the mutate pile that does is the top creature therefore all other creatures in the pile are not destroyed by Deed.

Yavimaya Coast, Woodland Cemetery, Ash Barrens are budget lands to consider adding.

Good luck with your deck.

Ooh thanks for more suggestions. I think right now I’ll need to playtest to figure out cards I don’t end up liking/using so I can then test out the many cards I have in the maybeboard.

The thing about infect is that there are a couple Blightsteel’s around in my playgroup, so a few smaller infect guys from my end isn’t a huge threat to the group. I’m also not too concerned with being archenemy anyways - I have an Ulamog, the Ceaseless Hunger deck that makes me number 1 threat when I play it, even though it’s not designed for 4 player games.

gotta throw out Cephalid Constable out there, great mutate target. good deck though!