Xenara, Antiquarian Thief

Xenara, Antiquarian Thief enters the battlefield
with your choice of a haste or hexproof counter.
Whenever Xenara deals combat damage to a
player, you may gain control of target artifact
that player controls with converted mana cost
less than or equal to the number of creatures in
your party. (Your party consists of up to one each of
Cleric, Rogue, Warrior, and Wizard.)