Tidewalker | Magic: The Gathering
Formats Tidewalker is Legal in
Official Oracle Text for Tidewalker
Vanishing (At the beginning of your upkeep, remove a time counter from this permanent. When the last is removed, sacrifice it.)
Tidewalker's power and toughness are each equal to the number of time counters on it.
Official Rulings for Tidewalker
2/1/2007 : If you don't control any Islands when Tidewalker enters the battlefield, its vanishing ability has no effect. (It enters the battlefield with no time counters on it, so neither of the vanishing triggers can trigger. See "Vanishing" in the General Notes section above.) On the other hand, it will be 0/0 and will be put into its owner's graveyard unless something is boosting its toughness.