Here is the full list of all 22 Edgar achievements.
Learned how to fly!
Defeated Can o' Bomb
Passed half of the underwater planet! Take a time to breathe!
Defeated Kroken
Learned how to inverse gravity itself!
Defeated Metal Edgar
Passed half of the candy planet! It's a pitty that Edgar is diabetic :(
Defeated Groody
Learned how to surf!
Defeated Lava Shark
The end is near...
Defeated Raguel
Sirus castle was easy, now fight him!
Defeated Sirus..... for real?
Made your way out of the first virus invasion
Made your way out of the second virus invasion
Made your way out of the third virus invasion
Made your way out of the fourth virus invasion
Made your way out of the fifth virus invasion
Made your way out of the sixth virus invasion
Passed the real Sirus castle
Defeated Sirus... for real!