There is only one giant moat monster, living in the castle moat. It has invaded Castle Daventry's moat and has been problem for the Royal Guard and King Edward, as its been attacking and eating the guards and knights of Daventry. They hope someone could come along and rid the of the pest.
Gwendolyn points out that there are fresh and seawater version of Moat Monsters. She also indicates that there are no Moat Monsters in her day. She wonders if they can be trained, but Graham tells her that is foreshadowing.
Some twenty years later after Graham had put the moat monster to work guarding the castle,and it was looking to retire.
There was however a new moat monster in Graham's senior years. But it was somehow gone by the time Gwendolyn hears the stories.
The species is a short stubby creature possibly with a shell on its back similar to a snapping turtle. It has a head that appears to be segmented form the shell/spinal ridges section. It only raises its head above water when a source of food falls into the water. Behind the shell/carapace/ridges lead into a thick short tail with a small fin at the end. It' snot possible to see but t here may be four sets of fins coming out of the middle of the body (there is only possible indication of a single fin on the right side when it is seen diving into the water with its prey), otherwise if it is finless it might resemble the mythological snake Tsuchinoko.