Seraphina by Rachel Hartman Tagged on: dragon shape-shifters expert musician half dragons half humans MC has secret identity
The House of Hades by Rick Riordan Tagged on: fell into other world half humans parallel stories from POVs of different sides
Dark Lord of Derkholm by Diana Wynne Jones Tagged on: bullied doorways to other worlds forced to fight to the death half humans teleportation
The Lightning Thief by Rick Riordan Tagged on: dead character lives half humans magic hat magic shoes MC discovers identity MC makes witty remarks progression of abilities in each book