Koyra of the Deep

Islandwalk
Tap four untapped Merfolk you control: Put a
land from your hand onto the battlefield. If that
land is an Island, you may put a flood counter on another target land. It becomes and Island in
addition.
{2}{u}{r}{g}: Creatures without Islandwalk get
-X/-0 until end of turn, where X is the number
of Islands you control.