For +7, +8, and +9/+MAX it'll cost 45 hero essence a SSS Ally, and 1,400,000 gold, 1,700,000 gold, and 2,000,000 gold, this will grant a 30% upgrade in stats for each of these upgrade levels.For +4, +5, and +6 it'll cost 30 hero essence, a SSS ally, and 800,000 gold, 1,000,000, and 1,200,000 million gold respectively this will grant a 20% upgrade in stats for each of these upgrade levels.To enhance the dark souls for upgrading to +1, +2, and +3 it only takes 15 hero essence to upgrade, as well as the above mentioned SSS ally, and 500,000 gold, 600,000 gold, and 700,000 gold respectivly, this will only increase the dark soul's stats by 10% each time.To enhance a dark soul it'll cost 1 SSS ally (does not need to be enhanced in any way), the same as limit breaking, 500,000 Gold (Enhance cost reduction does not effect this amount) and a varying amount of essence's depending on Upgrade level.To enhance a dark soul key you must go to the dark soul screen and click the enhance button after creating the dark soul.Ragnarok the warrior dark soul can only be equipped on the warrior player character and Warrior class deity allies, for the list of those currently in the game visit Ragnarok's section, the same is true for the Rogue dark soul only being equippable on the rogue character and deities, the Priest dark soul on the priest character, and priest deities, the Paladin dark soul on the Paladin character, and paladin deities, the Archer dark soul on the Archer character and archer deities, Mage dark soul on the mage character, and mage deities and the Incanter dark soul on the incanter deities.The dark soul keys can only be equipped onto player characters and allies that are acquired through the deify option and only if they are of the same class as the dark soul itself.However this does not mean that it can be upgraded by using U or SSS tier items as you would a normal item, however that is covered in the next section.The dark soul key will be added to your inventory where it can be thrown into storage like a regular item and can be equipped and unequipped from any diefied ultimate ally or character of the same class without consequence, penalty or gold cost.However just for clarity's sake I feel the need to make it clear that the gold and essences ARE consumed in the creation of the Dark Soul Key.These ULTIMATE allies are just a checklist for creating the Dark Soul Key, they are not consumed and lost in this process, they are merely required to make sure you don't make the Dark Soul without having a proper ally set to use them beforehand.Tyr will require ULTIMATE Tainted Loki, Dragon Slayer Lucienne, and Envoy Fulson as well as 1 million gold, and 30 Hero essence.Ragarok will require ULTIMATE Refuge King Gram, Power Sword Ackard, and Absolute Protector Patta as well as 1 million gold, and 30 hero essence.To make these dark souls you must have all 3 of their corresponding Awaken Allies at +ULTIMATE, 30 Hero essence, and 1 million gold to just create the dark souls key.In the allies screen on the right side you'll see two new circles on of which looks like a gundam of some sort, clicking on this will bring you to the dark souls screen where you create and enhance the dark souls.
If you want a version of this post specific to Dragon Busters visit my post with all of that info here. As well as the entire DB Discord for helping me edit and refine this info a little further, thanks for all your help. I'd like to thank Amarantine for helping me with some questions about Tyr I had that needed clearing up and helping me understand how Tyr effected KR when she was released there.