Here is the full list of all 21 Rock of Ages 3: Make & Break achievements.
Beat Poseidon in a race.
Complete all the Humpty Dumpty challenges.
Defeat Moby Dick
Get a bronze medal in all time trial levels.
Defeat the Vitruvian Man.
Rescue the Dragon.
Land in the highest scoring hole in the Skee-Boulder ramp.
Win a match of Boulder Avalanche or War without letting the enemy touch your door.
Destroy the enemy boulder using the thundercloud.
Win an online match of Obstacle Race.
Get a silver medal in all time trial levels.
Get a gold medal in all time trial levels.
Win an online match of War.
Rate a map from the Community levels.
Collect all the stars from the story campaign.
Follow all of Napoleon’s directions in the level editor tutorial.
Earn the Squire's medal by climbing up in the ranking system.
Earn the Knight's medal by climbing up in the ranking system.
Earn the Lord's medal by climbing up in the ranking system.
Earn the King's medal by climbing up in the ranking system.
Earn the High King's medal by climbing up in the ranking system.