Monster Analysis: Giant Sewer Rats

Thanks to @fwishb0ne for this art piece!

  • First Appearance: 2-10 Waste and Webs
  • Armor Class 12
  • Speed 30 ft
  • Darkvision 60 ft, Passive 10
  • Suggested Average, Max HP: 7, 12
    • Rat 1: 10 killing blow by Fjord
    • Rat 2: 10 killing blow by Fjord
    • Rat 3: 15 killing blow by Nott
    • Rat 4: 8 killing blow by Beau
    • Rat 5: 19+ taken, 13+ HDYWTDT by Nott
    • Rat 6: 7 killing blow by Jester
    • Rat 7: 7 taken, 5 killing blow by Caleb

Nothing screams beginning level D&D dungeon like giant rats. Although hardly a challenge and merely an appetizer for a much more terrifying main course, the diseased creatures swarmed would-be sewer travelers who did not heed the clumps of waste and refuse in the tunnels. Their matted and filth-coated fur not only spoke of the disease that they contentedly bathed in, but also of the refuse that fell from the city above. The lowly remains of trash and necrosis were funneled from the upper classes of the Tri-Spire to the lower classes of the streets above, then further down to these tunnels below.

While the rats mostly followed the Monster Manual’s suggestions for giant rats (including the diseased variant, p327), the poison effect from slashing and piercing damage was appropriately homebrewed to add to the grotesque nature of their necrosis. The party took a combined 17 points of damage from the poison effect of the ballooning beasts. This added an extra wrinkle to the battle (for the ones who were paying attention), resulting in Yasha putting away her axe and Molly shying away from his blades in favor of straight up punching rats.

Even after the initial swarm, enough evidence lay scattered throughout the rest of the sewers to indicate the giant rat population remained largely intact. However, the people of Zadash that secretly use the sewer for travel are apparently experienced enough with the rats to generally avoid them, as the halfling “ale runner” confirmed in response to Nott’s warning.