Sleeper Agent
{B}
Creature -- Phyrexian Minion
3/3
When ~this~ enters, target opponent gains control of it.
At the beginning of your upkeep, ~this~ deals 2 damage to you.
Treacherous Pit-Dweller
{B}{B}
Creature -- Demon
4/3
When ~this~ enters from a graveyard, target opponent gains control of it.
Undying (When ~this~ dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)