Normal Summon both Nordics, Link both into Gullveig, use the 2nd Gullveig to Special Bursti + Ivaldi + Black Goat, use Ivaldi to add Svalinn, use Bursti to add Dverg from GY to hand, and Synchro an Aesir of choice, preferably Thor to where Gullveig points to
As such this list seems to have favourable matches against aggro, midrange and control for the most part
Their own Level 10 Slime monsters that search out a Spell/Trap card related to them could be a good start, but they'll need different Special Summoning conditions to differentiate them from Guardian Slime
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That said, if the rest of the Uncharted Secret Lair drop has support for this new Commander, he could be quite compelling
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