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Since all the combos require my commander to instantly win, a quick n' easy way to do this would be just to swap Niv-Mizzet, Parun out with a noncombo commander and call it a day: Niv-Mizzet, Dracogenius is a straightforward swap if you still want to keep The Firemind in your command zone, or you can switch to another Spellslinger commander like Kaza, Roil Chaser
So instead, I'll just play Sarkhan as a big, fat, Dragon beater who threatens the other stuff
Jokes aside, there are about 4,000 human cards printed across all colors, including artifact humans and enchantment humans, and here were going to rank the best human cards Magic has to offer