Yrden

{1}{p/u}{b}, sacrifice this token: Tap target creature
you dont control, then distribute up to 2 stun counter among creatures your opponents control

Overload {4}{p/u}{b}, sacrifice this token
(You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")
Activate only if you control a permanent named Petri's Philter