<Snipped quote by Snarfulblast>
Then try to write it as something that could be avoided if within their characters' abilities. If I wanted a general ice power, like Killer Frost or Iceman, I'd write something like this: "Pounding his fist to the ground, the surface of ice seemed to nearly instantaneously reach to his enemies' feet and legs. Only the very agile or strong could break this kind of frost spell before it completely encased their bodies!"
Something like that, it sounds powerful, but you've written that it can be avoided if the other posters are creative enough.
^^ Exactly.