Call of the Bloodmoon

At the beginning of each combat step, before an
attack is declared, flip a coin. If you lose that flip,
all you creatures get -1/-1 until end of turn. If you
win that flip all creatures you control gain +1/+0
and Trample until end of turn and flip again.
If you win this Second flip you may pay {p/b}, if you
do sacrifice Call of the Bloodmoon and create
a 6/5 Rokahn Darkson legendary creature token
with Flying and Trample.