Kingfisher

Kingfisher enters the battlefield with a tide counter on it.
At the beginning of your upkeep, put a tide counter on Kingfisher.
As long as there is exactly one tide counter on kingfisher, it has -1/-1. As long as there are exactly three tide counters on kingfisher it has +1/+1 and islandwalk. Whenever there are four or more tide counters on kingfisher, remove all tide counters from it.
All fear the true king of the sea