I was thinking.
Q rework.
decrease the rate of turn of the blade down to like his joke, speed.
Darius visually prepares his axe for a milli-second.
He spins around himself dealing instant damage in a cone in front of himself, then dealing damage all around him. (Not like live were he deals instant damage all around himself). The ability take a full second to complete the 360 spin.
The axe will spin towards his left if the cursor is to Darius's left.
The axe will spin towards his right if the cursor is to Darius's right.
Damage is still smaller than blade damage.
Cancels movement. To compensate increase range (radius) by 10 or 20 units.
Passive could deal a little bit more damage for more compensation.
I'd rather not delve into his ability scalings too much.
I like the fear addition though. I feel like Garen should get something similar to that as well, seeing as his ultimate looks impressive.
Something like.
"Upon successful execution, Garen's ultimate now blinds all nearby units in a 700 radius for 2 seconds."