The vizier of poisons teaches an unconventional kind of strength

> Introduction

Hello, name's Slezy and I've been playing Hapatra pretty much since she came out. This particular deck went through a lot of iterations from casual token strategies to tuned list you can see above.
This is a high powered combo deck leveraging it's commander as a combo piece as well as stax piece and token generator. It tries to either win through one of the combo lines or just grind out the game with the bunch of deathtouch snake tokens.

> Combos

Yawgmoth lines

"Whatever Yawgmoth marks, dies. There is no escape."
—Tsabo Tavoc, Phyrexian general

The best card in the 99 synergizing with our commander is undoubtedly Yawgmoth, Thran Physician. Together they can create creature lock, along with card draw limited only by our life total. We need one disposable creature to start this loop, where we sacrifice said creature to Yawgmoths ability, put -1/-1 counter on an opponents creature, triggering Hapatra to get a new snake token to that we can again sacrifice to restart the loop.

What if opponents run out of creatures tho ? Well, we have 3 options.

1. Increase our own creatures toughness, so we can sacrifice one and put -1/-1 counter on another but it won't die yet. Then we can sacrifice creature with a -1/-1 counter on it and put fresh counter on the new token.
   This can be accomplished with cards like Metallic Mimic, Spidersilk Armor, Blex, Vexing Pest, etc.
2. Create more tokens than we sacrifice with cards such as Nest of Scarabs (along with our commander), Parallel Lives, Doubling Season, etc.
3. Negate the minus counter on a creature with plus counter. For this to work we need either creature with undying (Young Wolf, Strangleroot Geist, Butcher Ghoul) or stuff like Ravenous Squirrel, Ivy Lane Denizen, Woodland Champion, Blade of the Bloodchief...

From those options this deck currently runs Ravenous Squirrel, Young Wolf and Nest of Scarabs. Wolf and Squirrel are the most mana efficient and since they are creatures they can be tutored with every tutor we run. Squirrel also gets around graveyard hate cards. Nest on the other hand is quite expensive and harder to tutor, but it can work as a second copy of Hapatra which justify its inclusion.
This pretty much creates Yawgmoth's Bargain where we pay 1 life to draw a card. Captivated yet ?

OK, that's cool and all, but after drawing 40 cards we will be dead. Or won't we ? Hapatra and Yawgmoth are not only drawing cards, but also triggering death triggers and placing -1/-1 counters. With cards like Zulaport Cutthroat, Obelisk Spider, Poison Tip Archer, Bastion of Remembrance or Relic Vial we can not only draw our whole deck, but effectively drain the opponents for their life, while maintaining our own.

I don't recommend running Blood Artist without Endurance or something similar for this effect, because it can hit only one opponent at a time and since this whole line is limited by total cards in our library, there may be a case where we simply can't drain all 3 opponents with him.

Witherbloom Apprentice combo

With Strixhaven came new two card combo in golgari colors that is simply too good not to run with individual pieces advancing our main gameplan as well. This deck uses life as a resource a lot and even a bit of lifegain from Witherbloom Apprentice can make all the difference when digging with Yawgmoth. Chain of Smog is a great disruption with raw draw power in form of Necropotence, Yawgmoth and so on, that usually negates Chains downside for us.
Combo itself is rather easy. We need Witherbloom Apprentice on the battlefield and cast Chain of Smog targeting ourselves. This triggers Witherbloom Apprentice pinging every opponent for one. As Chain resolve, we may copy it targeting ourselves again and establishing the loop where we ping all opponents to death.

Note that this combo is rather dangerous as opponents can wait till we have zero cards in hand and then disrupt it by removing Witherbloom Apprentice, so be wary of timing when to go of.

Blowfly Infestation lines

Blowfly infestation serves essentially as a second copy of Yawgmoth. It may not draw cards but along with Hapatra/Nest of Scarabs and two X/1 creatures you can get infinite death triggers and infinite -1/-1 counter placements as well. Add Zulaport Cutthroat effect and you are draining your opponents as you would with Yawgmoth.

Note that you need a way to interrupt this combo, otherwise game ends in a draw. There are two ways to do so.

1. If there is a creature with 2 or more toughness (such that it won't die from the -1/-1 counter), target it with Blowfly Infestation's ability. Usually Hapatra herself serves as a target.
2. In case you have Nest of Scarabs instead of Hapatra on the field, you can order the triggers so that Blowfly Infestation's ability resolves before Nest's. If there is exactly one X/1 creature on the battlefield and this one is the target of Blowfly Infestation's ability, then it will die, trigger Infestation again, and this ability will be removed from the stack because there is nothing to target. If there are multiple X/1 creatures on the battlefield, repeat this process keeping Infestation's trigger at the top of the stack at all times until there are no more creatures left to target - after which you'll get a bunch of tokens from however many times Nest triggered while you were doing this.

Devoted Druid lines

The weakest combo line in the deck is Devoted Druid with Ivy Lane Denizen and our commander. It creates an army of infinite deathtouch snakes and also infinite mana if druid isn't affected by summoning sickness. We need to put the -1/-1 counter on the Druid triggering Hapatra, giving us the snake token. This will trigger Ivy Lanes ability to put +1/+1 counter on a creature, in our case the Druid. Rinse and repeat.

Note that we can activate Druids ability even if it's affected by summoning sickness, we just can't tap it for mana.

This combo was removed in favor of Witherbloom Apprentice line, since it is more mana efficient. Ivy Lane Denizen was a dead 4 CMC card most of the times.

You can find version of this deck on 165$ budget here.