Oracle Text

Whenever a player casts a black, red, or green creature spell, it gains devour 5. (As the creature enters the battlefield, its controller may sacrifice any number of creatures. The creature enters the battlefield with five times that many +1/+1 counters on it.)

Whenever you roll H, create two 1/1 red Goblin creature tokens.

Card Rulings

6/1/2012 Casting a multicolor spell will cause the first ability to trigger as long as that spell is black, red, or green. It can be other colors as well.
6/1/2012 If the creature spell already has devour, you may sacrifice creatures using either ability. Each creature you sacrifice counts for only one devour ability. Under most circumstances, you’ll pick the devour ability that gives the greatest number of +1/+1 counters.