So, I managed to get the legendary loot from Jailer Hylis (the final boss of The Renegade). It gives a bonus to attack power, a bonus to attack speed, and a stacking bonus that increases attack power with every melee hit, up to a max of 10 stacks, and at 10 stacks the innate bonus attack power of the item is effectively doubled, with no sort of time limit indicated on it. To me, this sounds a little too good to be true. Any character with more melee attacks than just quick melee could get a very large bonus out of this (with mine, a potential attack damage bonus of ~16.6 percent with max stacks, in addition to a ~5% attack speed bonus).
To anyone else out there who’s gotten this item (if anyone has), is there any limiter on the stacks besides the maximum of 10? Do they vanish over time, or vanish when the player stops using their melee attacks? I’ve been using it on all of my melee characters (and Caldarius), and it does seem to be making a big difference, but I could just be imagining it. I mean, earlier today I beat out an Oscar Mike in damage output with Kelvin. He might have just been a bad Oscar Mike, but still.