From Discworld MUD Wiki
|Learnt At||31 levels of magic.items.held.staff,
41-42 levels of magic.spells.special
Octograve is a command that lets a Wizard use a staff or a walking stick to make an octogram. The focus of an octogram is required for the casting of some spells. The glowing octogram is left on the ground to fade with time. Only a single octogram will appear in a room at a time, but it can be refreshed endlessly.