Here is the full list of all 20 PHAT PHROG achievements.
Unlock the Frozen Phlam costume
Unlock the Pirate Phlam costume
Unlock the Pharaoh Phlam costume
Unlock the Neenja Phlam costume
Achieve 1000 points on Challenge 3
Achieve 1200 points on Challenge 3
Achieve 1500 points on Challenge 3
Achieve 2000 points on Challenge 3
Achieve 250 points on Challenge 1
Achieve 1000 points on Challenge 1
Achieve 500 points on Challenge 1
Achieve 150 points on Challenge 2
Achieve 250 points on Challenge 2
Achieve 350 points on Challenge 2
Achieve 500 points on Challenge 2
Achieve 150 points on Challenge 1
Reach a high score of 10,000
Reach a high score of 7500
Reach a high score of 5000
Reach a score of 2500