@pionoplayer understood regarding your decision to not allow effects based on post numbers.
However in light of this I feel as if Lúin should be reworked or at least rebalanced, when I initially created it a key factor I was balancing around was the amount of damage vs. the time it takes for that damage to be applied and the ability to prevent it. With the time it takes to deal damage now, which is effectively 10 times as long Lúin was originally intended to take, Lúin is now to be blunt garbage tier. In comparison to another 20 charge weapon oilstone, Lúin has less uses, has about a 50% chance of dealing less or equal damage (assuming a Desended is triggering oiled) and in most cases will activate much, much slower. I wouldn't ask that the current mark on JOEbob change due to the fact that would be unfair for him however personally I feel that some buff is necessary due to how sheerly underpowered Lúin is.
So possibilities would include decreasing the time it takes to activate to say two rounds, increasing the damage tremendously (even if it instakilled an enemy after 5 turns it would still be pretty bad IMO) increasing the number of uses or making the damage unstoppable and just on a time delay. One or a combination of these would probably make Lúin more viable.
Ultimately however if you want to do anything at all is up to you.