There are a maximum of 29 Aarklash: Legacy achievements worth 727
124 tracked gamers have this game, 7 have completed it (5.65%)
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 12 tracked gamers (10% - TSA Ratio = 3.21)