Thread:JakCooperThePlumber/@comment-18812574-20170103024622/@comment-18812574-20170104192542

Most spells are graded on a scale from 1 to 99, spells of the latter being the most powerful and the most difficult to perform.

So how can you have a kidou then that is more powerful than the most powerful kidou that exists? 1-99 is the ranking system used by the Gotei 13. It's how spells are organized, and 99 is stated to be THE most powerful.

Forbidden Kidou is its own category.