Sacrifice?

[Apathy Reactor]

can you sacrifice any creature you control at any time, or does it have to have a sacrifice ability? my friend gains control of my creature for one turn, and then says he sacrifices it, is this legal?

[Double-O-Scotch]

No. You need what is known as a sac outlet. See {falkenrath aristocrat} or {ooze garden}

You need a spell or permanent to give you the option to sacrifice a permanent.

[Agarrita80]

Only if he sacrifices it using a another card that allows him to sacrifice the creature I.e : {Cartel Aristocrat} you can't just sac a creature just for fun that wouldn't be humane.