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.
During big fights in the arena or gladitorial ring between two well known or important warriors. When one looses and dies, the crowd throws copper coins into the arena for the slain warrior to take with them on their passage of death. This is to make their passage and afterlife richer and less troubled. It is a sign of respect.