Imprisoned Doom Rat

Deathtouch, menace
At the beginning of your upkeep, you may
sacrifice a land and draw two cards. If you don't,
sacrifice Imprisoned Doom Rat and you lose life
equal to the number of lands you control.
Sacrifice another Rat you control: Imprisoned
Doom Rat gets +X/+0 until end of turn, where
X is that creatures power.