Power-leveling is absolutely BROKEN

[Kiote]

I honestly think a mechanic as simple as, You must inflict a negative effect on an enemy to obtain experience points, would fix this problem. Conjurers need a reason to do more than stand around curing, and PLs would be encouraged to fight along side their friend rather than fighting for them.

[Soukyuu]

I honestly think a mechanic as simple as, You must inflict a negative effect on an enemy to obtain experience points, would fix this problem. Conjurers need a reason to do more than stand around curing

No, thank you. CNJ has enough to do healing it's party and keeping an eye on enmity and MP, with current MP costs for nukes, CNJ can empty their MP pool in about 12 combos (single target) or about 6 AOE hits. That's without healing.

Even with blissful mind/shroud of saints, you'd be sitting at 0 MP pretty fast. You should know this since you have leved CNJ to level 40.

What they do have to do is fix the claim system to transfer the claim to the party once a player who claimed the mobs leaves it, which would break the fastest oust/invite method. Yes, it wouldn't stop people from killing high level mobs from outside the party, but you won't be able to do it too fast because of mobs killing the party too fast/them having to recover.