You have access to four different types of Support Items:
- Airstrikes - Direct a precise military strike to toast large groups of Creeps
- Reinforcements - Drop in a platoon of Infantry troops to slow the enemy down and defend key areas
- Cryo Bombs - Freeze enemies in place for a short time
- Fusion Cells - A powerful battery that will give you extra Energy to build Towers
You can use your available Support Items by selecting them from the four icons in the bottom left corner of the screen during a level.