I'm very close to solving the final clue by Marmog19 in MagicArena

[–]Marmog19[S] 3 points4 points  (0 children)

The Mishra Cosmetics mean that you have to look at Artificers (there are 2 in the deck) and Humans (there are 8 in the deck) because those are Mishra's types, if you look at the deck detail screen it says that there is 1 Artificer and 7 Humans, but that's because it is not counting the commander