Tehg'irr, Bonewrought Horror

Tegh'irr, Bonewrought Horror enters the battlefield with nine -1/-1 counters on it and nine 0/1 black skeleton horror creature tokens. It can't attack or block when it has a -1/-1 counter on it.
Trample, Reach, Menace
{t}, {b}{b}, sacrifice a skeleton: remove a -1/-1 counter from Tegh'irr, Bonewrought Horror.