The Harry Potter movies were good to a lot of monsters: hippogriffs, grindylows, giant spiders. But they were really good to snakes. It’s one thing to watch National Geographic—Is that even on any more? Am I dating myself?—and see snakes lording it over rodents. But it’s anther thing to see Nagini punch through walls with her head and watch the plaster rain down. These snakes aren’t quite at that level yet, but all it takes is a template…
In the baths of Kemakhet, jars are brought to patrons filled with soaps, salts, and sponges harvested at the seashore and long dried in the sun. But since the baths are also run by an assassin cult, the jars sometimes contain constrictor snakes, typically sand boas. The boas kill the target—usually a political enemy, occasionally a random sacrifice—and return to their jars. The servants quickly learn never to complain about jars that leave the chambers heavier than the arrived.
The so-called flying snakes of the Hool Jungles can glide from tree to tree. Certain venomous red-bellied varieties don’t just use this method for travel—they launch themselves at prey and strike even before they land.
Orc shamans, especially druids and oracles, tend to have all sorts of animal pets and mounts. But snakes are reserved for orc sorcerers (and especially for the exceedingly rare orc wizards). Some of this is custom—the sinuous serpents seem mystical to orcs, who read portents from their tracks and scale patterns. But some if it is also survival. Being the slightest bit frail or bookish can single one out for death in an orc clan, so having a venomous friend can be a literal lifesaver. (The bonus to Bluff checks doesn’t hurt, either.)
—Pathfinder Bestiary 255