I have blown threw 30 bosses. I have came up with a theory that the further along you get, the percentage to get an uncommon or a rare increases. I have proven my theory correct
Level 1-20
13 commons(65%), 5 uncommons(25%), 2 rares(10%)
Level 21-40
5 commons(25%), 12 uncommons(60%), 3 rares(15%)
I am going to keep beaten Ramon until time runs out to get more loot
Please share your results In this format to help prove or disprove my theory, Or share any thoughts regarding this.