Riptide Island
From March of the Machine Commander set
Riptide Island
Plane — Dominaria
When you planeswalk to Riptide Island and at the beginning of your upkeep, create two 1/1 colorless Sliver creature tokens.
Whenever chaos ensues, Slivers you control gain haste and get +X/+X until end of turn, where X is the number of Slivers you control.