Maze Rats conversion for Skerples' Monster Overhaul

I saw a query recently about modifications to the simple Maze Rats rules by Ben Milton. I used these rules for a long-running fantasy campaign (30+ sessions). I also used The Monster Overhaul (2023) as my bestiary throughout, when I didn't invent my own monsters.

I thought I'd just share this recipe.

The conversion from the Monster Overhaul to Maze Rats so easy that there is no reason not to use the Monster Overhaul book, if you have it, as a bestiary for Maze Rats on your own. It boils down to this:

Maze Rats	Monster Overhaul
Attack score	Hit Dice halved, round down
Health Points	Hit Dice doubled
Armor 6	Armor: none
Armor 7	Armor: as leather
Armor 8	Armor: as chain
Armor 9	Armor: as plate
Armor 10 (or 9)	Armor: as plate + shield

If you like tougher monsters and/or longer fights, Maze Rats HP equal Monster Overhaul hit dice tripled.

If you want Strength, Dexterity, and Will scores for a monster, decide based on the fiction: bigger and stronger monsters have higher strength, etc.

Huge monsters do an extra point of damage with a hit, like a two-handed weapon.

Small monsters do one less damage with a hit, like an unarmed attack.

If a monster has special attacks, you may want to trigger them when it rolls doubles. Require PCs to make the appropriate saves for monster special effects.

You can easily fiddle with the rest, but this is all it takes to work.