Double Flash is an upgrade from the Slush Invaders: Game which allows Staddison to increase the stun time of his flashbangs to 4 seconds. It costs 20,000 points.
- This upgrade has an Area of Effect ability in which it can stun any nearby enemies surrounding the target it explodes on.
- Much like Stedro's Blaster, Double Flash cannot stun Bosses. However, it can stun the Ether Lord when his Shield Health goes down but cannot if his Shield Health is still up.
- Strangely, it can also stun the Bluish Fighters, but does not cause them to stay still. Instead, the stunned Bluish Fighter will still disappear to the side of the screen after being hit.
- Although the name may suggest it, this upgrade can sometimes mislead players into thinking that upon being bought, Staddison may throw two flashbangs instead of one.