Arcanemage t20 2 set nerf?

[EmiHes]

So I got my new 2 set bonus today, and I noticed the duration was only 6 seconds. When was this nerfed? I don't see any posts about it. It used to have a much longer duration, and now I barely get 3 casts in while the buff is up. The damage buff part of the set feels kind of useless atm. The 4 arcane charges is nice though.

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Don't quite see why they nerfed it, since arcane needs all the help on singeltarget dps they can get.

[Deleted]

It was set to 6s like 2 months ago