Here is the full list of all 36 Danger Ducklings achievements.
Perfect Level 16
Beat W1-1
Beat W1-5
Perfect W1-23
Beat W1-30
Beat W2-1
Perfect W2-9
Perfect all World 1 Levels
Perfect all World 2 Levels
Perfect all World 3 Levels
Beat W2-30
Beat W3-1
Hit the retry button 10 times after failing or completing a level
Fail a level
Perfect every level
Unlock 25 cosmetics
Equip a cosmetic
Unlock all construction duck cosmetics
Unlock all wizard duck cosmetics
Unlock all astronaut duck cosmetics
Unlock all holiday duck cosmetics
Unlock all duck cosmetics
Use the Undo button 20 times in one level
Beat W3-30
Unlock 25% of Concept Art
Unlock 50% of Concept Art
Unlock 75% of Concept Art
Unlock all Concept Art
Complete 25% of Time Trials
Complete 50% of Time Trials
Complete 75% of Time Trials
Complete all Time Trials
Perfect all World 1 Mastery Levels
Perfect all World 2 Mastery Levels
Perfect all World 3 Mastery Levels
Complete the Credits