“ On a location with numerous webs, and at least one big spider, there is a something inside a cocoon. It is humanoid in shape, still moving. If the heroes free it (not before they kill or drive away the spiders), they meet a ... zombie!
The poor zombie wandered the dungeon alone, and tried to kill a big living creature (= a spider). The spider used the usual treatment, even if this victim did not look tasty. The zombie can be easily killed as any other zombie. It got but several doses of spider-poison, so can be something worth if it is extracted. You can mention to a druid or ranger the fact the spider had no poison anymore.”
“ A magic speaking sword of great power-which is also a racist, obnoxious and unpleasent, so much so that those who carry it often *gag* the hilt of it, the taking part, with cloth to shut it up.”
“ An army and navy who work in the same way as others except their rank titles are upside-down. So people start as full generals and those with the rank of private command armies.”