Shifting Dimensions

This is it, I present to you the core mechanic of MULTI-SPACE! The thing that I pin all my hope on to make my game unique. Without this, my game merely consists of waves of enemies. What will make it different? I'm assuming you've read the title of this post, so here it is! The ability to transform from their 2D sprite into a 3D character!

But why? Well the aliens will spawn in the masses, surrounding the player from all directions, leaving them no choice but to shift dimension. The benefit of this is the ability to move through walls as the 3D character plods along the flat surface of the 2D scene. Of course the aliens can still nip at their feet as they wander above them, so they must still be careful not to get too close. 

One major drawback of the dimensional shifting technology is the lack of defence it provides. Yes they can escape tricky situations with ease, but for a brief time they are rendered defenceless as their weapon is left behind. In a two player game, the players must work together. One action from one player will affect both. Communicate before forcing your friends body into another dimension!

The technology only has enough energy to last a few seconds before the player is brought back into 2D, and naturally it will require a short cooldown before its next use. This should be used sparingly, especially in the heat of battle!