(: Add or to your mana pool.)
At the beginning of your upkeep, Gilt-Leaf Underground deals 1 damage to target creature you control.
: Gilt-Leaf Underground becomes a 2/1 green and black Squirrel creature until end of turn. It's still a land.
: Add 
or 
to your mana pool.): Gilt-Leaf Underground becomes a 2/1 green and black Squirrel creature until end of turn. It's still a land.
