Purchase any upgrade.
Reach a score multiplier of 9.
Destroy a total of 250 enemies.
Destroy a total of 500 enemies.
Destroy a total of 1000 enemies.
Pick up a total of 100 gears.
Pick up a total of 250 gears.
Pick up a total of 500 gears.
Ride every hoverbike at least once.
Defeat your first boss.
Unlock one additional boss.
Purchase all upgrades in one category.
Defeat every boss at least once.
Defeat any boss without taking damage.
Purchase all upgrades.
Reach wave #5.
Reach wave #10.
Destroy a total of 2000 enemies.
Pick up a total of 1000 gears.
Fully upgrade both main weapons.
Destroy 10 enemies by crashing into them.
Pick up 30 gears in one attempt.
Unlock a new background.
Destroy 5+ enemies with one katana slash.
Reach wave #3.
Reach a highscore of 5000+ points.
