The current exploit meta abusing 2 Berserk Tokens and Uncreator Psalms is out of control and it is fair to say they need to be re-balanced and soon.

It is really easy to destroy the mechanics as viable if not properly approached.

Fortunately, it is actually pretty easy to re-balance both of these exploited mechanics.

1) UNCREATOR PSALMS

Suggestion: Don't allow these to stack at all. 

Problem solved, and still a viable mechanic/buff to add to your build.

2) BERSERK

Pre-seasonal patch the token limit did not exist, and with the seasonal patch this was dropped to 150 tokens max. the berserk mechanic by itself isn't broken per say until you abuse equipment rolls that can stack to be out of control.

Currently the only enchantment that breaks this mechanic is found on signums and it gives up to 6% damage per berserk token. This is a stacking bonus that can hit +1800% damage, effectively making the game a cake walk and not challenging in the slightest.

So this enchantment needs to be cut down or changed.

Because Enraged has similar enchantments but off of a maximum stack of 10, yous till manage to get several hundred percent extra damage if that is all you focus with an enraged build in terms of enraged bonuses, and it isn't that broken, it's fairly balanced all things considered. But with1 50 tokens to play with, even on 2 items only, this breaks the game.

Suggestion 1: Change the damage percentage to 1 (ONE) Percentage Point per berserk Token, for a maximum of 150% extra damage on each signum or 300% total damage. 

This is still overpowered to my mind as your other item slots are still open for critical hit chance and strength and other effects working off of berserk, whereas with enraged to get the high damage stacks, you forfeit other benefits.

This leads to...

Suggestion 2: Change the Enchantment on the Signums to be a flat damage bonus regardless of how many berserk tokens you have. I'd go with +30%. This is in line with pre-existing bonuses to specific damage types such as against poisoned enemies, against stunned enemies etc. +60% damage bo9nus from 2 signums whilst berserk alongside the 150% damage increase from max stacks of berserk is 210% damage bonus. It's quite significant but not over powering.

Suggestion 3: Replace the 1% damage Reduction per Berserk Token with 1 Suppression Regeneration per Berserk Token. 

Damage Reduction is supposed to be hard to get. Berserk eliminates that. Suppression manipulation has been challenging for a lot of people (not all of us mind) since Augmented Body 2 changed. This gives you up to 150 extra suppression regeneration at any one time, a significant amount that will allow people to play the hit and run style that the game tries to encourage, a lot more and to retain effectiveness of extra abilities in suppression state green. It's also more fluff friendly as when you go berserk and rage you still take damage, you just fight through the pain to ignore being slowed down or otherwise hampered, having high suppression regeneration allows this to happen by preventing being stunned etc.

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The danger Berserk in particular faces right now is that over-nerfing occurs to make it an unviable strategy to even contemplate - obsolete mechanics are not what we want in the game. The above suggestions would make it still useful, still powerful, but not overwhelmingly so.