Sappy, the Forgetful

When Sappy, the Forgetful enters the
battlefield, investigate. (Create a colorless Clue
artifact token with "{2}, Sacrifice this artifact:
Draw a card.")
At the beginning of your upkeep, you may
discard a card. If you do, you gain 2 life and
investigate.
Whenever you sacrifice a Clue, regenerate
target creature.