a dozen? she literally scooped all of the larger sentinels up in the first episode with a tornado with so much control she didn't harm her teammates....
I could imagine that a few X-Men are leaving the team and joining Magneto. Rogue for sure, maybe Beast, and even Cyclops (for shock-value). Colossus...
This thread makes me wonder: how does the average Viltrumite fair against the average Namek in battle? How many Viltrumites would it take to conquer...