Prevent is a special ability used to preempt (stop) another card’s special ability. In order for a prevent card to stop the special ability of another card, it must be played before that card. A prevent card is unlike interrupt and negate cards because it cannot undo a special ability on a card that has already been played. Prevent takes precedent over “interrupt” when the prevent is played first. (For example, Captain of the Host says that all special abilities except for banding are interrupted and prevented. If he is blocked by King of Tyrus, whose special ability negates all abilities, Captain of the Hosts special ability is not negated since it is already preventing King of Tyrus special ability). This ability stops things that have not yet happened. It cannot undo things that have already happened.