Pick Your Poison

Sorcery

Choose any number of modes that total exactly 4. You may choose the same mode more than once. [1] Put a +1/+1 counter on target creature. [2] Create a 1/1 black Snake creature token with deathtouch. [4] All creatures get -2/-2 until end of turn.

A reliable, general-purpose toxin is a handy way to save on belt space.