Here is the full list of all 24 Snailiens achievements.
Buy your first weapon in the SALT Base
Buy all available weapons
Buy your first tower in the SALT Base
Buy all available Towers
Destroy your first Snailien
Pickup your first Power Up
Throw your first Krabber
Build your first Tower
Defend your farm from the Snailiens
Arrive at SALT HQ
Defend Main Street
Defend the Courtyard of the State Fair
Save the State Fair
Defend the Corn Maze
Protect Town Hall from the Snailiens
Defend the Crop Circle
Revisited your Farm
Started Walking the Payload to the Temple
Bring the Payload to its Destination
Held back the Army of General Klang
Defended the Courtyard of the Temple
Completed All Current Levels
Recieved a Perfect Score on Every Level
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