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Use a slingshot (UK - catapult) to aim ammo at the enemies to stop them from escaping from prison. The catapult can be moved and rotated in all directions, in order to accurately aim at the enemies' bodies.

There are three difficulty levels: easy; medium, and hard.

The enemies will try and defend themselves, using their prison trays. If your ammo hits one of the trays, the enemy will spawn, and a new enemy will be created. If too many enemies are created, you will lose. The game is also lost if an enemy crosses the finish line.

Enemies will be killed if you hit them with the ammo, or else if they step onto ammo lying on the floor. If you kill all the enemies you win.

There is a help page containing videos, which outline how to play the game. It is highly recommended to look at them, especially the helpvideo 'Aiming'.

Older devices with an API level less than 30 will download a Legacy version. The gameplay is the same; however, the graphics (especially special-effects) are inferior to those on newer devices. API level 30 came out in Android version 11 (2020).
This is because older devices do not have the necessary GPU power, leading to jerky/slow gameplay. Both versions cost the same, since Google Play do not allow different prices for different versions.
What constitutes slow gameplay is subjective, and will also depend on the hardware of the particular device. It is also the case that some Android 10 versions may be updated to API 30. If you think the version downloaded is incorrect, please contact us to obtain a different version.