One reason the file persists is modding. The later game updates encrypted the asset files (Unity3D). Version 1.0.9a left the asset bundles largely open.
patch cycle focused on addressing player feedback regarding the game's steep difficulty and grind. Key changes included: Balance Adjustments MISTOVER.v1.0.9a.rar
Class balance was broken in 1.0.9a. The Rogue (Dagger user) is overpowered due to an uncapped backstab multiplier. Later patches nerfed this; version 1.0.9a rewards aggressive flanking. One reason the file persists is modding
In version 1.0.9a, the tutorial dungeon will kill you. You must replay the first Cathedral area (Area 1) multiple times to grind levels 1-5. Do not attempt Area 2 until your gear is blue rarity. MISTOVER.v1.0.9a.rar