“ Draw the party together as debtors to the local lord, king, head of the thieves guild, or mercenary clan, who is forcing them to work together to pay off their debts.”
“ 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.”
“ Thieve's House or thier main front: All the floors are designed to squeak when stepped upon or to sag or bend sending a small shake along the beam, somewhat like a spiders web, to alert those inside.”