I suggest to raise Twisting Slash from range 2 to 3. *This solves many issues that cannot be solved, and thus does not generate a disadvantage against the rest of the classes, such as the Elf which has an exaggerated triple shot range, etc. Some reasons:
The majority of spots have ranged mobs
mobs stay fixed at the floor (he don't move after spawn) for a some mins
some mobs spots stay at close range of the BK twisting slash and don't die, they don't loose HP (the same, for some mins, then he move and die, but this take too much time maybe 10 o 20 mins)
some mobs spawn at right range of twisting but they run away and hit from distance
Thanks for hear us! and i wait for a reply. Video Examples: Close Range issue:
TwistingSlash range2 issue: