Tidal Influence

Play Tidal Influence only if no permanents named Tidal Influence are in play.
Tidal Influence comes into play with a tide counter on it.
At the beginning of your upkeep, put a tide counter on Tidal Influence.
As long as there is exactly one tide counter on Tidal Influence, all blue creatures get -2/-0.
As long as there are exactly three tide counters on Tidal Influence, all blue creatures get +2/+0.
Whenever there are four tide counters on Tidal Influence, remove all tide counters from it.