Patty and Jordan, Bros

: During your upkeep, Knight Proliferate (Choose any number of Knight creature you control & give them another counter of each kind already there.)
+1: Put a +1/+0 or a +0/+1 counter on target creature, and as long as it has a counter, it is a Knight in addition to it's other creature types.
-10: Remove all counters from creatures you control, and do that much damage to target player.