The Monster Codex is broken up into two sections. The first being Type, which is broken into Reaver,
Breaker, Swarm, Occultic, Command, and Leviathan. Reavers are monsters who are usually quick and attack with sharp attacks like claws, teeth, and blades. Breakers are monsters who usually are very large, durable, and slow; fighting with blunt and powerful attacks like crushing fists, heavy stomps, and bony tails. Swarm monsters are monsters that move in hordes, swarms, or deal with nests and hives and attack in massive numbers to make up for their often smaller size. Occultic monsters are monsters who have a great connection to The Other and always have magical properties. Command monsters are leader grade monsters that can have subordinates in the other types, yet to qualify for this type the monster in question must have noticeable differences from their lesser counter parts. Finally Leviathans, which have to Categories as they all follow the same level of danger and are great beasts with a very wide variety of strength and powers.

Next section is the Danger Category that has six levels. Category 1, monster is docile and poses no threat or danger to others. Often cowers and feels when presented with danger. Category 2, docile and peaceful, but dangerous when provoked. Category 3 is hostile and low threat. Category 4 is hostile and medium threat, meaning they are a challenge to beat and shouldn't be fucked with. Category 5 is hostile and serious threat, which means these guys are a danger that should be treated with the utmost care and dealt with by a team when the monster is isolated and with heavy weapons that include rocket launchers and heavy machine guns. Category 6 is hostile and unsafe threat. This category is the one you pray you never see as they are the worst of the worst with dense natural armor, great speed, and vicious attacks. If you engage a Category 6 you'd best have a tank and even then still hope that it doesn't reach you as it could probably open that tank up like a tin can.