Here is the full list of all 19 Rock of Ages achievements.
Get a gold medal on all maps in Time Trial mode.
Destroy a flying ship.
Win a War game using the Cube.
Win a match using the Snowball boulder.
Beat the game in Story mode.
Find all the keys scattered throughout the levels.
Destroy your adversary’s boulder.
In SkeeBoulder, land your Boulder in the maximum multiplier.
Earn more than 7000 gold in one match.
Win 10 online War games.
Score a direct hit on an enemy boulder with the Castlepult.
Win a match with your gate unscathed.
Win a match without destroying any of your adversary's units.
Win an online War game
Land a projectile on some TNT to produce a shockwave combo that hits your enemy.
Hit the castle gate with the fireball powerup.
Break off the second layer of your adversary’s boulder.
Break off the first layer of your adversary’s boulder.
Complete the tutorial level and escape from the underworld.