Change Legendary chance to pseudorandom

[Malong]

Personally, my ideal loot system would be similar to NKP, except it wouldn't rely on kills, but instead being present for spawn waves / to fully complete the run. 
A way to present this would be to give 5 (x) for completing a full run (all 5 spawns), and each spawn is 1 (x). So, if somebody joins on wave 6 and completes the run, they get 3 (x). It's not a full run, so they don't get rewarded for joining way late, but they still get something out of it, and it's effectively fair.

I think we are presenting the same idea:

Basically you would get points for bosses that you have spawned. For example (using ragnarok), you could get 10 * number of the boss, and 150 nkp for participating all 20 waves in a successful ragnarok server.

Though I added the idea of weighting bosses differently with a toy example as "number of the boss." Taking out the coefficient for the game mode, Heimdallr would be 1 point, Hodur and Tyr 2 points, ..., Odin 5 points. Using your example (and again removing any coefficient for game mode), someone carrying out a full Ragnarok game would get 15 points, and someone spawning in at wave 7 would get 12 points.

I don't know how many (x) you would need to get a legendary, but it'd have to be a fuck lot, as to not flood the market with legendaries and make them worthless.

I put forth an abstract form of projecting rarity and weighting a required number of boss deaths here:

You could also allow hoarding these for the very ra[r]e boss drops in tiers that require 100, 200, 300 successful runs, which will take anywhere from over a month to multiple months for even the most hardcore players.