Caxus, Thornsreaper

Trample, menace, unconquered (this creature
can't be countered, discarded or exiled.)
Whenever Caxus attacks you may pay {x}{g}{g}. If you do, untap X target creatures you
control and there is an additional combat phase
after this one.
{x}{x}{x}, {t}: Create X 3/3 black and green cactus minion creature tokens with menace.