(Grassy Ampitheater isn't a spell.)

Whenever Grassy Ampitheater becomes tapped, it deals 1 damage to you.

Grassy Ampitheater is indestructible. (Destroy effects and lethal damage don't destroy it.)

: Add  or to your mana pool.

Put Grassy Ampitheater on top of your library: Add  to your mana pool.