Not sure if this is new this patch, but it gives Honor EXP when you use it. I got 5xx 3 times and one gave 756.
A Cannon I looted with Additional Options. The orange +x means how much above average it is, not just if it's from Additional Options, so you'll see the +x next to anything that's above average on an item, such as defense. Item names that are above average are normally Blue. This is Purple indicating Rare (?).
Above Average Level with Options
An above average level item I found. Note the Gold colour for the name and the +32 INT. Too bad it sucks.
Desperados apparently drop. Looks pretty neat.
The stats above the class requirement are PDEF, MDEF, Boss Damage, and presumably Defense Ignore. So if they stack non-linearly, you would be able to tell here before equipping the items.