Slaetherus, The Abyssal Horror

Deathtouch, hexproof, first strike

If an opponent attacks with more than ten creatures at the same time, Slaetherus, The Abyssal Horror, loses hexproof until end of turn.
{2}{b}{b}: put a -2/-2 counter on Slaetherus, The Abyssal Horror and give a creature under your control deathtouch.