War Cube (Steam key/Region free).

http://store.steampowered.com/app/527800/
War Cube is a strategy game, each team is on a face of the cube and the player must turn sideways to position your troops so that they stop in an attacking position, being behind or beside the enemy.

There are two game modes, Battle and Convoy.

In Battle mode, all sides of the cube are against you, be the only survivor.

In Convoy mode, your goal and defeat all enemy soldiers but at the same time protect the team that is disarmed, a soldier killed unarmed results in a failed mission.