Here is the full list of all 23 WUFO achievements.
Who has let him in?
Defeat Boss 1
Defeat Boss 2
Defeat Boss 3
Defeat Boss 4
Defeat Boss 5
Defeat Boss 6
Defeat Boss 7
Defeat Boss 8
Finish the game
Complete 100% the game
Abduct Wi-Fi 1000 times
Abduct Wi-Fi 2000 times
Abduct Wi-Fi 3000 times
Destroy 500 space items
Destroy 1000 space items
Destroy 2000 space items
Why did you do it? :(
Are you going to hold it?
I think I've seen a cute kitty
woof, woof!
You are muscled now
Artificial intelligence?