Numa, Joraga Chieftain

Hexproof
At the beginning of your upkeep, create a 1/1 Elf Druid with "{t}: Add {g} to your mana pool"
{x}{g}{g}: Put X +1/+1 counters on target Forest. It becomes a 0/0 elemental
"A single tree does not a forest make. We are stronger when we stand together."