This thing is sick. Compare it with Merchant of Secrets.
No, most creatures do not have evasion (trample is not evasion), and in any case it's irrelevant - this card is designed to be sacrificed.
IMO, it needs to cost at least 2U or 3U.
Scapegoat Familiar
3U
Creature - Pinata
0/1
When Scapegoat Familiar comes into play, draw a card.
When Scapegoat Familiar leaves play, draw a card.
You never know what might fall out.
We already made a pinata creature (and I hate it, btw) but that was funny.