Pawn

A deck can have up to eight cards named Pawn.
When Pawn enters the battlefield, put a Charge! counter on it.
When Pawn attacks, remove a Charge! counter
from it. If a Charge! counter was removed this
way, it gains double strike until end of turn.
At the beginning of your end step, if Pawn
attacked this turn, put a One Step Closer counter
on it. Then if it has five or more One Step Closer counters on it, exile it and return it to the battlefield transformed.