There also are explicit guidelines (for magic spirits) on page 111 of RoP:Magic. Thankfully, they do match exactly. 
(And since I've found the search function to be capricious, I'll link to the other topical thread of the moment.)
There also are explicit guidelines (for magic spirits) on page 111 of RoP:Magic. Thankfully, they do match exactly.
(And since I've found the search function to be capricious, I'll link to the other topical thread of the moment.)