Here is the full list of all 20 Nexoria: Dungeon Rogue Heroes achievements.
Get Ending 1
Eat 33 meals
Find a new hero in dungeon
Get a 5 level
Defeat a boss
Kill the boss
Get a 2 level
Get a 10 level
Kill a mimic
Kill over 100 enemies
Complete three levels of the dungeon
Complete five levels of the dungeon
Defeat Nexoria
Defeat a Witch
Get Ending 2
Get Ending 3
Get Ending 4
Get Ending 5
Get Ending 6
Get Ending 7