Scravers - A "Mutant Future" Monster

We have to put our weekly Monsterhearts game on pause for a couple of weeks. I want to run something on the other side of the RPG spectrum to fill the gap, and I think I've settled on Mutant Future, a Gamma World homage from Goblinoid Games.

I needed some relatively low-HP humanoids to use as antagonists for the adventure I have planned. None of the monsters in the Mutant Future book were exactly what I was looking for, so I made up my own. Let me introduce you to the Scravers. Gotta' love me some rat-people.

Scraver
No. Enc.: 2d4 (6d6)
Alignment: Chaotic
Movement: 90' (30')
Armor Class: 7 (leather armor)
Hit Dice: 4****
Attacks: 2 (claws) or 1 (weapon)
Damage: 1d6/1d6 plus poison, or by weapon
Save: L3
Morale: 6
Hoard Class: II (XVIII)

Scravers are squat humanoid rodents that resemble bipedal shrews. They are known for their greed, cruelty, and cowardice. Their large, thick fingered hands are equipped with retractable claws that secret a paralytic venom. Scravers gather in small semi-tribal gangs lead by the strongest and cruelest of their kind. They prefer to live underground, in ruins, or the dark parts of the wasteland, trusting their echolocation and sharp sense of smell to guide them. Gangs of scravers often raid small settlements and caravans for food, loot, and salvage.

Scravers are cowardly, and prefer to attack opponents from a distance with bows, crossbows, or salvaged firearms. If forced into close combat, they attack with two claws. An opponent wounded by a claw attack must save against paralysis or become paralyzed for 1d6 rounds (Class 10 poison). The scravers' echolocation grants them a +2 to hit in combat. If a fight goes against them, scravers will use their venom to paralyze their foes and flee.

For every 6 scravers, there will be one 5HD sub-boss with AC 6 (studded leather). For every 18 scravers there will be a 6HD boss with AC 5 (chainmail) who saves at L4, and inflicts +1 damage in combat. There is a 50% chance that a boss scraver will be accompanied by a 5 HD savant with 1d3 beneficial mental mutations.

Scravers often breed and train giant rats for use as guard animals.

Mutations: Ecolocation, Increased Sense (scent), Natural Weapons, Toxic Weapon

XP
Standard: 300
Sub-Boss: 800
Boss: 1320
Savant: 950/1100/1250