Considering we're on a AFC forum, who'd you think I'd (Julius) ROOT for??
The People used brains in their fights. I mean, they gave Artemis Fowl a hard time, even.
This is assuming Opal does not sabotage the fairies.
Also, they're so high-tech, PLUS they have basic amounts of magic. Even though it requires the least magic, I feel the mesmer would basically seal it for them.