The Department for the Regulation and Control of Magical Creatures categorizes beasts, beings, and spirits into one of five groups to allow the curious a quick and to-the-point rating where the dangerousness of a particular creature is concerned. These categories are:
| XXXXX | Known wizard killer/impossible to domesticate |
| XXXX | Dangerous/requires specialist knowledge/skilled wizard may handle |
| XXX | Competent wizard should cope |
| XX | Harmless/may be domesticated |
| X | Boring |
The bestiary has been grouped alphabetically by the name of the creature.