Castle's Power

Where were you, the day life as we knew it ended, and magic returned to Earth in a rush? When goblins, undead, and dragons were restored? When the electric grid went down for the last time, and gunpowder stopped exploding? Cameron Castle was in the worst place he could have imagined: underground, in a stranded subway car, with magical monsters appearing in the darkness nearby. Worse yet, he's got a dozen kids with him, and if they can't escape the deathtrap the subway tunnels have become soon, they never will. Surviving the tunnels is only the beginning, though. This new, changed Earth will challenge Castle on every possible level. Boston is swarming with goblins, rocs, and an invading army of crustaceans out for payback. Welcome to the Magipocalypse. Come right in! Do close the door, though... The monsters are right behind you! (To read "The Accidental Necromancer, check it out here: https://www.royalroad.com/fiction/98578/accidental-necromancer These two stories happen in the same story universe at the same time, however, so you don't need to read one to enjoy the other!)