Loki, the Cunning

At the start of each upkeep, or when Loki,
the Cunning enters the battlefield, Loki, the
Cunning becomes a copy of target creature.
Except it also has all its abilities and name.
When Loki, the Cunning deals damage
to a player, you may transform it.
When Loki the Cunning dies, exile it instead
than return it to the battlefield at the
beginning of the next turn's upkeep.