Blazewreck Nightmare

Flash, First strike, Menace
At the beginning of combat on each player's
turn, they may pay 3 life. If they do, the
controller of Blazewreck Nightmare places a
-1/-1 counter on Blazewreck Nightmare.
This may only happen once per combat phase.
{3}{p/b}{p/b}, Remove a -1/-1 counter from Blazewreck Nightmare. Place a -1/-1 counter on up to
two target creatures.