Answer:
The characters from chapters 11-20 are
Milo
Tock
The Humbug
King Azaz
The Mathemagician
Dynne
Dischord
Soundkeeper
The Dodecahedron
The Everpresent Wordsnatcher
The Terrible Trivium
The Demon of Insincerity
The Gelatinous Giant
The Senses Taker
Hope this helped.