The Headless Horseman

Haste, fear
{t}: Add {b}. If there are six or more creatures in
all graveyards, add {b}{b} instead.
Whenever another creature dies, untap The
Headless Horseman. Put a +1/+1 counter on it.
"All these, however, were mere terrors of the night, phantoms of the mind that walk in darkness."