1. Do the parkour event on the event server next time so nobody have an advantage gear wise. 2. If you want to give a potion effect you can just have a command block under the starting plate that gives it to everyone. 3. Add a floor to the map, a big problem with the last pk event was that falling into the void would boot you out of the parkour, but if we just had some sort of floor, even one made of barriers, people could do /event checkpoint easily with no fear of falling out. 4. Limit the potion effects to speed, giving players jump boost will not only make the jumps insanely easy but it will also let players take massive shortcuts. Speed 2 however, will just make the jumps a bit easier but still have a competitive edge to it. 5. Try to build new PK maps, they don't even need to be fancy they just need to have lots of parkour. If you really want to include jump boost as a potion effect, this will help you see major skips/sequence breaks beforehand and you might even be able to design a section specifically for jump boost 3 (i.e. 3 high jumps) 6. Try to avoid slime blocks as I'm pretty sure the anti-cheat doesn't work well with them. Back in v9 I had a slime jump that worked fine until you updated the anti-cheat so I know it's that (The only reason you could do the slime jump in the pk was because you had OP & the anticheat wouldn't push you back).