Pashi, Wood Sneaker

Whenever Pashi, Wood Sneaker attacks, if
defending player controls creatures, they must put
a forest counter on at least one of them. Pashi
can only be blocked by creatures with forest
counters on them, and creature with forest
counters can only block Pashi.
Pashi, Wood Sneaker gets +1/+1 for each creature
with a forest counter on it. When Pashi, Wood
Sneaker leaves the battlefield, remove all forest counters from all creatures.