Enraged Hydra

Trample, Haste, Menace
{3}{r}{r}: Monstrosity 5 (If this creature isn't monstrous, put five +1/+1 counters on it and it becomes monstrous.)
{r}{r}: Destroy target non-planeswalker, non-enchantment permanent. Activate this ability only if Enraged Hydra is monstrous, up to 3 times per turn, and only on your turn.