Hamstersaurus Rex is a young middle-grade series written by Tom O'Donnell, about a quirky class pet that undergoes a transformation and helps defend a loyal sixth-grader from a werewolf-obsessed bully. 

'A certain pleaser where furry fictions are well-loved.' - Kirkus

'Adult and kids alike will find that O'Donnell's deadpan, mildly absurdist writing style will generate some satisfying laughs.' - School Library Journal

'Miller's zippy b&W cartoons are well-matched to the book's offbeat sense of humor.' - Publisher's Weekly

SQUIRREL ATTACK! Sam Gibbs and his super-strong tiny buddy, Hamstersaurus Rex, are back in this hilarious classroom comedy, perfect for fans of Dog Man and Stick Dog—and for anybody who might be entertained by a mutant rodent showdown.

Sam and Hammie Rex discover a terrifying giant squirrel hiding in the woods behind Horace Hotwater Middle School. But nobody else believes Squirrel Kong is real. 

Then Hammie Rex takes the blame for Squirrel Kong’s destructive rampages, and the principal threatens to send him away to home for dangerous, troubled small pets. To save his hamster friend, can Sam prove that Squirrel Kong is the true menace?

Expect mysterious mutations, deliciously gross snack foods, and an epic battle with the world’s most fearsome squirrel in this outrageously funny second installment in the Hamstersaurus Rex series.

“In the annals of class-petdom, few indeed could ever match aptly named Hamstersaurus Rex for loyalty and ferocity.” - Booklist

Mysterious hauntings are causing major trouble at Horace Hotwater Middle School. Sam Gibbs and his super-strong tiny buddy, Hammie Rex, keep encountering creepy abnormal objects, including a floating sports jersey and a runaway go-kart.

While Sam doesn't believe in ghosts, he has to admit the hauntings are getting weirder…and more dangerous. Could bizarre mutant animals be the cause? At Horace Hotwater, they often are!

Beware of furry ducks, slippery baked potato toppings, masked ninjas, and more in this laugh-out-loud mystery starring the world's coolest class pet.