Iv got a question, what would u wear? Existencial core +4 or Forbidden Core +4? I am lvl 32 evoker.

Without a doubt the Forbidden Core

Forbidden Core. Depending on your playstyle they might serve you up to level 55 as they have great power reg/power cost reduction and decent damage. The next tier of weapons are Mutentacles which I'm not that fond of myself because they increase the cost of your spells by 20%. Having Hellfire consume more than 100 power per cast is not my thing.

Okey, thanks for answer guys I will upgrade my weapons to Forbidden Cores

Try to get Forbidden Cores with 2 mod slots, it's worth it. Also if you have a big wallet you might want to take a look at the +%dmg before you buy them.