Creature — Elemental 6/6, 3{G/U} (4)
Uncommon
Sturdy Hatchling enters the battlefield with four -1/-1 counters on it.
{G/U}: Sturdy Hatchling gains shroud until end of turn.
Whenever you cast a green spell, remove a -1/-1 counter from Sturdy Hatchling.
Whenever you cast a blue spell, remove a -1/-1 counter from Sturdy Hatchling.
Illus. Darrell Riche

8/1/2008: If you cast a spell that's both of the listed colors, both abilities will trigger. You'll remove a total of two -1/-1 counters from the Hatchling.
8/1/2008: If there are no -1/-1 counters on it when the triggered ability resolves, the ability does nothing. There is no penalty for not being able to remove a counter.
Legal in Vintage (Type 1)
Legal in Legacy (Type 1.5)
Legal in Classic (MTGO)
Legal in Commander
Legal in Modern