Tentacle Swarm

As long as you control 6 or more islands,
Tentacle Swarm has split second. (As long as this
spell is on the stack, players can't cast spells or
activate abilities that aren't mana abilities.)
All nonblue creatures you don't control get
-X/-X until end of turn. For each creature that
dies this way, you scry 1. (Look at the top X cards
of your library, then put any number of them on the
bottom of your library and the rest on top in any
order.)