Mo never wanted to be a Warden - protecting the village of Bogfoss from the terrifying monsters in the woods is way too scary. But when he's beaten up by a goblin on his first patrol, he knows he has to prove himself.

So he sets out into the forbidden woods to catch himself a monster and make himself a hero. Instead he stumbles into GRUMPFORT, a secret monster fortress with a very big problem. The fearsome Grumpsnatcher is kidnapping the other monsters - and suddenly Mo's on a monster-hunt with a troll, a gnome and a fire-breathing snotwoggle to stop it!

'Grumpfort is brilliant! Thoroughly charming.' Louie Stowell, author of Loki

'Perfect for fans of How to Train Your Dragon and Grimwood.' Jennifer Bell, author of Wonderscape