I'm looking for the most powerful mage spell (not used in combination with anything). What spell deals the most damage, without considering the synergy they have with other equipment or strategy? Warmaster's Burst? Destruction Burst? Coloured pencils? Which is it and where can I find it? Please exclude special offers and rares.
Maybe the new Frostval delivery set spell. Unraveling Nightmare. Does x2 damage as well as being overcharged and dealing extra damage from HP cost. Although it's going to be a rare, you can still get it by doing the Frostval: All Alone quest.