Slinn Voda, the Starved

When Slinn Voda, the Starved enters the battlefield you may sacrifice any number of Islands.
Whenever you sacrifice one or more islands,
you may reveal that many cards from the top of your library, put any number of Merfolk, Krakens, Leviathans, Octopuses,
Serpents, and islands onto the battlefield tapped, put the rest on the bottom of your library in any order.
Slinn Voda's power and toughness are each equal to the
number of islands in your graveyard.