The Skeleton Army is about defeating an army of skeletons.
In this map, there are 2 magic pads: a purple and a blue one. If you stand on the purple magic pad, you will get strength and resistance for a short period of time, and if you stand on the blue one, you will get speed and regeneration.
You will use these to assist you with battling the skeletons. The magic can also be used to do things such as open doors and turn blocks into other magic pads.