After about a year, a long journey is near it's end, I got the privilege to show you a teaser of the new unique items I made, with a huge effort from the design team of GGG, the balance team, and the one and only, Hrishi, an amazing person that gave me the best service.What's the downside of belly ? of Yriel's Fostering ? of The Perfect Form ?

This item IS strong, but I don't think it'll be OP. It's going to depends on the new skills I think, and on how strong LT will become after becoming a channeling skill.
Belly- has great defensive mods yes, but you don't see players completely trivializing and laughing at endgame content scaling defenses like belly has. Sure you might be able to facetank or afk endgame content by building defenses, but this certainly doesn't allow you to continuously farm guardians/shaper in less than 4 seconds a stage because of the insane dps numbers and power that can be achieved in the game right now.
Yriels- yes this is offensive but 60% crit chance only grants a you a couple% effective crit chance, and it only applies to projectile attack skills, which makes it more specific to a certain type of character(a slight downside in itself, a limit, rather). Also, the other offensive based mods are conditional in that they require you to have minion summoned, if you want that minion to survive reliably without recast you need to invest in it a bit. Its like having another golem That always dies in good content unless you invest something into it. That is another prime example of a down side.....
Perfect form- also defensive, free aa and phase acro, and +evasion based on uncapped cold res, but wearing it effectively starts you at -90% cold res, so that -30% cold res is a down side right there. Also, nobody is killing shaper in 2 seconds cuz they're wearing perfect form.
One of the biggest problems they have is people making a joke out of content with some of the insanely powerful builds there are right now.
All I am trying to say is, this is a completely offensive based armor which is fine, but it seems REALLY strong if all of those numbers are + numbers. And I have a feeling with the use of a couple select items could make for some pretty stupidly op damage. From ggg's perspective, you would think they would try to balance some of the power that is way op, this prevents the rich from flooding the market with good items and lots of currency because they are insane fast and/or do 1billion dps so they can repeatedly do the most rewarding content at a fraction of the time intended. That is the reason I say I am surprised there is no downside to this. Seems like people will put out some serious offensive numbers with this.

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