You want to play in every game, and you especially don't want to be in the penalty box for five minutes and give the other team a chance to get a power play, and you don't want to hurt anyone on the other team.
I mean the word proof not in the sense of the lawyers, who set two half proofs equal to a whole one, but in the sense of a mathematician, where half proof = 0, and it is demanded for proof that every doubt becomes impossible.
I'm not constrained by being a genre writer. Any story I can imagine, I can cast as a fantasy novel and probably get it published.