Indomitable Hydra

Trample
Whenever Indomitable Hydra deals combat damage to a player, add that much {g} to your
mana pool. This mana doesn't empty from your mana pool as steps and phases end as long as you control Indomitable Hydra.
{g}{g}: Regenerate Indomitable Hydra and put a +1/+1 counter on it. Activate this ability no more than twice each turn.