There are a maximum of 29 Aarklash: Legacy achievements worth 691
92 tracked gamers have this game, 6 have completed it (6.52%)
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 11 tracked gamers (12% - TSA Ratio = 2.89)