Numenera is a game published by Monte Cook Games. Its setting is the Ninth World, and this list has ten rumours for that setting. The rumours, which are similar to the Use that can be found with creature descriptions in the official books, can be used as adventure hooks or as simple misinformation.

1. Erynth grask are ultraterrestrials with a practically incomprehensible intelligence. They are usually encountered singly, and are dangerous when so encountered, but some claim that there is a pattern to encounters with the creatures. Not just a pattern for the behaviour of an individual erynth grask, but for all of them, as if the entire species is acting on some sort of overarching plan.
2. Ghost crabs live on the ocean floor, but only in the deeper regions. They can be a danger to any who venture into the depths, as the hunt creatures for food, trapping them in their webs. Though ghost crabs grow up to 5′ across, there are rumours of even larger specimens found in the depths, ones which can grow two, three or even more times larger than even the largest typical ghost crab. These are also said to be substantially more intelligent.
3. Isthyns are known to fiercely defend their nests, even if doing so means that they will die. A nest of isthyns isn’t so easy to kill, though, and sometimes people harvest isthyn eggs and plant them in places where they wish to deny access to resources, allowing the eggs to hatch and riddling regions with the dangerous creatures.
4. Jiraskars are extremely dangerous, and fast, creatures, and an encounter with such can quickly end in death for all concerned. However, someone has decided that, because of this, jiraskars would be highly effective in combat. Which is likely true, but training one would be extremely difficult and dangerous. They are offering a reward for all jiraskars that can be captured alive, and an even bigger reward for any that can be trained.
5. Margr are known for their violent lives, killing each other or anyone unlucky enough to stumble across them. There’s a rumour of one tribe in the wastes, though, that has managed to rein in its bloodlust, at least when it comes to other members of the tribe, and are therefore growing in size and strength. If not stopped, they may become a significant threat to any settlements and caravans in the region.
6. Mastigophores are normally found in pairs, or larger groups, guarding ancient ruins from interlopers, standing watch and stopping anyone entering. There’s a rumour of some more mobile groups of mastigophores, that travel along regular routes, almost as if they are guarding a road or other ancient route that has now disappeared.
7. Mesomemes harvest the heads of their victims, whether human or animal, and attach them to tendrils that sprout from the creature. Most mesomemes have an assortment of heads from many different creatures attached to them, but there are rumours of the occasional one which is much more selective, only choosing heads from a specific type of being.
8. Most murdens live out in the wilderness regions, where they prey on passers-by, but there are rumours that some have set up homes in the tunnels and sewers beneath some larger cities. Though few claim to have seen them, or survived the seeing anyway, there are repeated claims of the irritating telepathy of the murdens being detected.
9. Nevajin are creatures that can separate their head from their body and have both parts still function separately, though this is a painful process. Someone wants to capture a number of nevajin and forcibly separate their bodies from their heads, to study just how far apart the two can survive, and is willing to pay substantial amounts to anyone who can capture the creatures.
10. The poisonous reptiles known as laaks are not particularly dangerous individually, but they are rarely found individually. A few people have been said to have turned up dead recently, seemingly poisoned by laaks, though none can be found on the premises. Leading to suspicions that someone is letting laaks into places to do their killing, then collecting them again.

Want some items that could be used as oddities? Check out 100 Xenoarchaeological Finds.