Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
Whenever Meandering Towershell attacks, exile it. Return it to the battlefield under your control tapped and attacking at the beginning of the declare attackers step on your next turn.
9/20/2014 As Meandering Towershell returns to the battlefield because of the delayed triggered ability, you choose which opponent or opposing planeswalker it’s attacking. It doesn’t have to attack the same opponent or opposing planeswalker that it was when it was exiled.
9/20/2014 If Meandering Towershell enters the battlefield attacking, it wasn’t declared as an attacking creature that turn. Abilities that trigger when a creature attacks, including its own triggered ability, won’t trigger.
9/20/2014 On the turn Meandering Towershell attacks and is exiled, raid abilities will see it as a creature that attacked. Conversely, on the turn Meandering Towershell enters the battlefield attacking, raid abilities will not.
9/20/2014 If you attack with a Meandering Towershell that you don’t own, you’ll control it when it returns to the battlefield.