Here is the full list of all 21 Rubber Ducky and the Rainbow Gun achievements.
It's there, it's unique! Just look closely!
Well, it's sorta' in the level. . .
This one's not too hard to find. . .
Looks like someone just likes firing the Rainbow Gun. . .
Well, it's still there. . . just less dire.
Be addicted to social media.
It's a practical paradise, just for you!
Play with Death Epileptic Pixel mode on. (There's also a game of the same name)
Convince/bother/bribe the dev until everyone gets this achievement.
Type the 2nd section of the dialog from the 6th level backwards into the cheat code selector! Don't forget to puncuate and capitalize properly!
You're the best! :D
Everyone knows it's the best part!
I told you to go right, didn't I. . .?
. . . or it would have been, anyway!
Have the game run below 30 Frames Per Second.
Buy all the costumes!
Unlock all the levels!
Beat the dev's score on the last level! (You might want to shoot for around 1500)
Place fifty-jillion (100) plants in the bounce house at once.
Get below 8:00 in speed run mode.
You've defeated the derpy brother and unlocked a message from the developer. . .