Maze of Icebergs

You may choose not to untap Maze of Icebergs during your untap step.
{t}: Tap target creature. That creature doesn't untap during its controller's untap step for as long as Maze of Icebergs remains tapped.
The Mariner's boat had become trapped in a maze of icebergs, some of whom were the size of the boat's
mast.