The knight slayer set is bugged: (5 items) Your fully-charged Heavy Attacks deal an additional 8% of an enemy's Max Health as Oblivion Damage. This can deal a maximum of 8000 Oblivion Damage.

If you dodge the heavy attack, you take the damage twice. I guess the proc is guaranteed and registered on heavy attack start. Then is somehow registered on the dodge because I guess you cannot dodge oblivion damage.

Please see the parse.