There are a maximum of 29 Aarklash: Legacy achievements worth 683
61 tracked gamers have this game, 5 have completed it (8.20%)
Start a new game in Rag'narok level of difficulty; then reach and kill Baron Mornstar without ever pausing the game. Make sure you disable the tutorial and the automatic pause options.
Unlocked by 8 tracked gamers (13% - TSA Ratio = 2.76)