Here is the full list of all 26 Overrogue achievements.
Cleared the Beginners' Cave.
Cleared the Scream Peak.
Cleared the Brownie Street.
Cleared the Overlord Castle.
Cleared the Zareos Ruins.
Cleared the Osay Forest.
Cleared the Tempuraly Avenue.
Cleared the Gaap Hall.
Cleared the Gamijin Cliff.
Cleared the Gushion Palace.
Cleared the Pekoe.
Cleared the Tower of Trial: 5th Floor.
Cleared the True Overlord Castle.
Defeated 50 enemies.
Defeated 200 enemies.
Defeated 500 enemies.
Cleared the Labyrinth 10 times.
Cleared the Labyrinth 50 times.
Cleared the Labyrinth 100 times.
Upgraded cards 10 times with the Upgrader.
Upgraded cards 25 times with the Upgrader.
Upgraded cards 50 times with the Upgrader.
Drew the Sagan Gacha 10 times.
Drew the Sagan Gacha 50 times.
Drew the Sagan Gacha 100 times.
Cleared all quests.