Here is the full list of all 17 Riptale achievements.
Beat the Mushroom Caverns
Beat the Crypt
Clear a room within a single combo, with a minimum of 5 kills
Beat the Underground Forest
Beat the game on normal mode
Buy one of every gem type during a single playthrough
Beat the Crypt without taking damage
Beat the Underground Forest without taking damage
Beat the Mushroom Caverns without taking damage
Beat the Ancient Ruins without taking damage
Kill the Necro Dragon without taking damage
Kill the Fire Dragon without taking damage
Kill the Twins without taking damage
Kill the Dragon Overlord without taking damage
Beat the Hard Mode
Collect all pets
Collect all trinkets