Datamined DRK changes from final build

[Brannigan]

So what's the point in having Darkside as a buff if it costs no mana

Disables outside MP regen. They could just make it a trait (MP regen stops in battle, outside sources don't work, dmg increased by 15%) but you wouldn't be able to toggle that off for cases like A12S where there's no enemies on the battlefield for a full 45s but you're still in combat.