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Galaxy Defense (Android)

Galaxy Defense Screenshots

Android version

Title screen
A showcase of the available towers.
First levels are simple enough.
Buying upgrades between levels.
...Or you can buy the in-game currency with real money.
A new type of tower is introduced.
The shield protects our structures.
This level introduces flying enemies. It's also around this point that the game becomes so hard that you're basically required to shell out real cash to stand a chance. Clever.