Tidal Influence

Cast this spell only if no permanents named Tidal Influence are on the battlefield.<br>Tidal Influence enters with a tide counter on it.<br>At the beginning of your upkeep, put a tide counter on Tidal Influence.<br>As long as there is exactly one tide counter on Tidal Influence, all blue creatures get -2/-0.<br>As long as there are exactly three tide counters on Tidal Influence, all blue creatures get +2/+0.<br>Whenever there are four or more tide counters on Tidal Influence, remove all tide counters from it.