The Impossible Quest Series by Kate Forsyth

Tell your lord to beware; the wolves smell danger in the wind . . . Wolfhaven Castle has been attacked, and only four escape capture... Tom, trained to scrub pots, not fight; Elanor, the lord's daughter; Sebastian, a knight in training; and Quinn, the witch's apprentice.Somehow, if they are to save their people, these unlikely heroes must find four magical beasts from legend and awaken the sleeping warriors of the past. But first, they have to make it out of the castle alive...