If the basement is not air-tight, the gaseous water would quickly flow out of the cracks, finding a level which is quite plausibly low enough for the creature to have no difficulty in breathing when the water becomes fully substantial. Again, it would clearly see the rising mist and would react appropriately. When the gaseous form effect ended, the water should probably return to its liquid state; even if the monster can still breathe, it would likely be at some penalty for being in water up to its waist/shoulders (depending on how generous a GM you are). Depending on the creature, either of those may be significant penalties, or they may be fairly minor inconveniences.
Adventure Lookup is a catalog of adventures for Dungeons and Dragons and its clones.
We need your help to expand the catalog and ensure each entry is reasonably accurate.
Simply create an account to start adding adventures or submit change requests!
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to be promoted to a curator.
Matt Colville first talked about the idea in a video of his in 2016. It wasn't until August 2017 before the site went live .