I hope that this will be the first in a series of articles taking a monster as inspiration for adventure and/or encounter creation. Monsters are one of the things D&D made me most exited about and to this day, I have problems to ignore monster books no matter the system they are written for. So there are already a lot of critters out there waiting for me to mull over them.

Out of curiosity (once again), I picked up Octopus Games‘ Free Monster of November 2015, the Giant toxic sponge. This CR 5 monster lives at the bottom of the sea and is surprisingly mobile for a sponge. Main abilities are Siphon, with which the sponge creates a current drawing its prey towards itself and Swallow Whole (up two two creatures). Its Toxic Aura causes acid damage and may poison its prey. As long as you’re interested in underwater adventuring, it’s actually a nice little critter and the only thing I’d probably change is the poison-induced ability damage (from DEX to STR; the Save against the Siphon ability is strength-based so it would make sense to me if the Toxic Aura would attack the same ability, making the monster a little bit nastier .

And as this is what I’m most interested in (thinking about how to use the stuff I’m reading about), here are some ideas how to use the Giant toxic sponge.

1. The PCs are tasked to retrieve some treasure from a ship sunk before the coast during a heavy storm. Unluckily, the ship’s body has been infested by a pair of Giant toxic sponges feeding from the fauna living near the wrack. They won’t surely mind greater prey (like some meaty PCs for example who will literally have to go through the sponges to get what they came for.

2. When some townspeople go missing and the local authorities aren’t able to find any clues about their whereabouts, the PCs are hired to solve this riddle by the brother of a wealthy merchant who hasn’t been seen for several days. Hints point to a nearby lake and the PCs may find that the missed persons fell prey to a giant advanced toxic sponge. How did a salt water creature get into a sweet-water lake. And how is it able to survive there? The answers to these questions may lead to a mass murderer on the loose thinking he had found a way to commit the perfect crime.

3. For mysterious reasons a portal to the water plane opened in a big mountain cave looming over a little town. Poisonous Water pouring through the portal threatens to destroy the town but finding a way to close the portal involves exploring the cave. Meaning to handle the creatures coming through the portal as well as handling the portal itself which seems to be a gigantic living creature drawing the water out of the plane of water onto the material plane.