Rare items don’t seem to be set items. So maybe you can only get set items from the arena? I don’t know.
I’m a little fuzzy on how they are different from other items.
I noticed that max levels on items has changed. 5 star set items can go to 230 now, not 180. 6 star set items can go to 270. Skill effects on rings now seems to be 15%, not 20%.
Edit since I can’t make more than 3 comments:
I do not seem to be getting email rewards from megapass or arena fights.
Filters can go to 6 stars now and you can lock items so they won’t be sold (nice). But they need to have checkboxes for rarity levels.
Not enough resources makes it harder to test things out.
I like how the new itemization looks, assuming set gear doesn’t dominate everything (set gear is very boring in terms of itemization at least if it is all the same).
Also noticed Epic Items in the Stele, which I was not able to get (no more crystals 
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I assume energy cost increases for the glyph mine and other things are meant to make things slower.
Edit2:
The S/A/B/C ranks on gear stats, I assume that is about growth. It’s a bit confusing for mixed gear items. When a physical defense B is twice as big as physical defense B and magical defense B on items with the same stars, it makes me not sure what exactly this ranking means.
I have a Physical Defense B, Magic Defense C, Dodge RTG A item. The Physical Defense number is the same as on the two-stat helms of the same stars, but half of what it is on the uncommons with one stat. So do all of those ratings increase slower than you would find on an item with just one rating. How big a difference is that at level 10 or 100? Why do the defense scores suffer like this? Is the dodge rating lower than it would be on a dodge-only item? Is it half of what a dodge RTG A would be if it was by itself?
This is very confusing and counter-intuitive. I suggest it might be easier if you found a system where the rating alone indicated the growth (e.g. say a rank D was half the value of a Rank A, so you’d just have two rank D stats on mixed items instead of a Rank A) or you indicated if something was being halved or otherwise modified. As it is it is hard to tell how good something is or what the ratings are going to mean when you have multiple stats on one item.
Also, I fond a rare ring with only Speed C – that shouldn’t be happening, right?
I notice all the old set gear is rank S on the stats, which has me worried that we’re just going to aim for set gear in the end.
Edit Again! (New Poster limitations):
So some of the new set items just need 2 pieces and affect a skill like Last Stand: Power effect +20%. I think this is a better system since it encourages mixing different gear together. But it looks like some of the old set gear still shows up in the market.
Not sure if it is intended, but the Arena Chest might need to be modified if there are now far more sets to potentially get. Before I was able to work pretty well on 3 or so sets, while prioritizing one. Now it seems like you might easily get just options that aren’t helpful (I have no mages with Arcane Barrage, so the set gear for that is too much – and the class change is too expensive for me to try on a whim to see if it would work). Especially true if you might get an item for a set but it might not have the stats you want (I don’t know if that can happen or not though).
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