Yoshi

{1}{g}: Create a 0/2 Egg creature token with
Defender and "{t}, Sacrifice this creature: Proliferate 1".
{1}{g}{g}: Yoshi gets three +1/+1 counters,
Trample, and 2 time counters. Remove 1 time
counter at the beginning of your upkeep.
Whenever the last time counter is removed,
Yoshi loses three +1/+1 counters and trample.
As Long as Yoshi has Time Counters, it cannot
use mana abilities.