I bet mixing stacking vulrability de-buffs, AoE's that have 360 degree knockback that pertrafiy (with added vuln de-buff), tankbusters that always take a tank to 1hp with an added bonus of the ground having a random direction toss mechanic (think spring loaded floor pads that also add vuln-stacks) that activate when u walk on them while lit for a walled arena (no-wall seams to unfair but make it so half the floor is lit at all times) & just make it DF solo-qurry only... the sear amount of cowardination between randoms for something that f't up would be legendary, but maybe doable (as long as it "NEVER" got nerfed)

that or just bring back origional Steps of faith with a forced "min ilv" & lv sync... that murdered the player base so much they nerfed it outa fear for their sub numbers, still in most cases solo-DF runs can be far worse than a pre-nerf EX if the fights hard enouf normally with PF