This stage recreates the structure in front of the helipad on Shadow Moses Island.

High walls on the left and right?!

Walls tower over the stage on the left and right, giving it a caged death-match feel.

The searchlight spots someone, and the "!" icon appears!

You can destroy the walls on the left and right with attacks. Those who aren’t skilled at launching foes upwards may want to be proactive about attacking them.

The walls come tumbling down.

Oh, and occasionally a Metal Gear will appear from the background.

Metal Gear REX!

Metal Gear RAY!

Apparently one other kind appears, too. It’s supposedly a slightly newer model.