Greater Werewolf

At end of combat, put a -0/-2 counter on each creature blocking or blocked by Greater Werewolf.

Skeleton Ship

When you control no Islands, sacrifice Skeleton Ship.
{T}: Put a -1/-1 counter on target creature.

Whenever you cast a spell, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Enchant creature
Whenever enchanted creature becomes tapped, put a -0/-2 counter on it.