All Those Explosions Were Someone Else's Fault — James Alan Gardner

Monsters are real.
But so are heroes.

Sparks are champions of weird science. Boasting capes and costumes and amazing super-powers that only make sense if you don't think about them too hard, they fight an eternal battle for truth and justice ... mostly.

Darklings are creatures of myth and magic: ghosts, vampires, were-beasts, and the like. Their very presence warps reality. Doors creak at their approach. Cobwebs gather where they linger.

Kim Lam is an ordinary college student until a freak scientific accident (what else?) transforms Kim and three housemates into Sparks―and drafts them into the never-ending war between the Light and Dark. They struggle to master their new abilities―and (of course) to design cool costumes and come up with great hero-names.

Turns out that “accident” was just the first salvo in a Mad Genius's latest diabolical scheme. Now it's up to four newbie heroes to save the day, before they even have a chance to figure out what their team's name should be!