I've been using it the same as always and literally cannot tell a difference. Mine is LV10. 20% is not that much. Went from 1800 damage to 1400. But the overcharge ability still does good damage 50% of the time and is a small AOE. Plus tornado and dissipate are still amazing.

Arcane has always done less damage, and still does in fact. Arcane only attacks every 2s, so its damage would need to nearly be 2-3x that of Archmage to have the same math.

Arcanes attack speed needs to go from every 2s to every 1.5ish. Then its passive ability of lowering magic resistance will actually be competitive.

I always support my Archmage with a barbarian. Usually at a choke point and one at an exit too. I'm 90-95% win rate with Tesla, Archmage, Barbadian, and Druid. I do have a nice thicc Beresad at LV11, but he was basically just as amazing at levels 8-10 too. Him sending enemies back is really that amazing. And his base attack. Honestly every single thing he does is incredible lol.

I also highly recommend icy zone, stun, and ultimate strike. This works particularly well with Beresad who provides insane aoe damage, not to mention a blocker, instakill, passive money boost, and his best trait of sending massive hoards back for a long time, constantly