Tiamat

Flying, Protection from Monocolored

Whenever a Dragon you control attacks, choose one for each color among Tiamat’s heads

{w}: You gain 3 life.
{u}: Draw a card.
{b}: Each opponent loses 2 life and you gain 2 life.
{r}: Tiamat deals 3 damage to any target.
{g}: Put a +1/+1 counter on each Dragon you control.