Here is the full list of all 21 Rock of Ages 2: Bigger Boulder achievements.
Cross the Dragon's sea once without falling into the water.
Earn the High King's medal by climbing up in the ranking system.
Earn the King's medal by climbing up in the ranking system.
Earn the Lord's medal by climbing up in the ranking system.
Earn the Knight's medal by climbing up in the ranking system.
Earn the Squire's medal by climbing up in the ranking system.
Get a bronze medal in all time trial levels.
Get a silver medal in all time trial levels.
Get a gold medal in all time trial levels.
Win the match against God without letting him score any goals.
Collect all the stars from the story campaign.
Win an online match of Obstacle Race.
Win an online match of War.
Destroy the castle doors using the Block of Ages.
Land in the highest scoring hole in the Skee-Boulder ramp.
Win a match of War without letting the enemy touch your door.
Destroy the enemy boulder using the thundercloud.
Defeat the Sphynx without losing any boulders.
Defeat the Dragon without losing any boulders.
Defeat The Thinker without losing any boulders.
Win a match of War using only animals to defend (cows, whales, lions, bulls or elephants).