Everythingamajig (a)

[2], [Tap]: Move a counter from one permanent onto another. If the second permanent refers to any kind of counter, the moved counter becomes one of those counters. Otherwise, it becomes a +1/+1 counter.

[3], [Tap]: Put a +1/+1 counter on target creature.

[4], [Tap]: Proliferate. (You choose any number of permanents and/or players with counters on them, then give each another counter of a kind already there.)