Clacker

Trample
Cumulative upkeep {r} or {g} (At the beginning of
your upkeep, put an age counter on this permanent,
then sacrifice it unless you pay its upkeep cost for
each age counter on it.)

Clacker gets +1/+1 for each age counter on it.

Not...as I...ap..appear," the monster tried to explain
in its halting speech.- Exile