Threat Ratings.
When people described the dangers of the monster, they would either give out the information about its mana core or the number of mana shells it had.
Of course, such kinds of information sufficed in terms of describing the sort of dangers the monster posed. However, for those unaware of the monster's true extent of destructive capabilities, it proved rather ineffective.
Thus, the Threat Ratings were created.
With the use of mathematical values and multipliers, they were able to create a sort of table.
Mana Shell stages were assigned points 1 to 7.
Wretch, Gnarl, Maw, Husk, Gore, Reaver, and lastly Dread - each one given an assigned value with an increment of one.
Then, you had the level of the monster's mana cores, which added a multiplier ranging from 1.0x to 2.5x.
Feral (E), Savage (D), Dire (C), Prime (B), Great (A), Apex (S), Colossus (SS).
And the categories of destruction went like this: