Originally, I wanted to build a giant, five-colored zoo deck featuring Vampire Bats, Manta Rays, Stampeding Rhinos, Mountain Goats, and Savannah Lions
Of course, since youd be playing black, cycling all these creatures into the graveyard gives you plenty of reanimation options, such as Reanimate, Victimize, and even Rise of the Dark Realms
Mega Greninja's existing fanbase keeps engagement constant even without viral pull moments.
You also need to make sure you hit your land drops, either with draw effects (Qiqirn Merchant and Adventurers Airship provide usable bodies as well as draw smoothing) or cards that directly give you lands or mana (World Map, landcyclers, Blitzball)
While N is usually 1 or 2, there are cards with toxic 6 and even 9, so beware: if you get 10 poison counters or more, you're dead no matter how high your healt may be