Here is the full list of all 15 Restless Hero achievements.
COLLECT 10 GOLD INGOTS.
COLLECT 25 GOLD INGOTS.
COLLECT 50 GOLD INGOTS.
DESTROY 25 ENEMIES.
DESTROY 55 ENEMIES.
DESTROY 100 ENEMIES.
FINISH 5 LEVELS.
FINISH 15 LEVELS.
FINISH 30 LEVELS.
GET 5 MEDALS.
GET 15 MEDALS.
GET 25 MEDALS.
UPGRADE 3 POWERS.
UPGRADE 5 POWERS.
UPGRADE 10 POWERS.