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.
The journey had been a long one and now they had entered the mountains. After an entire day spent on paths cut into the mountainside and through moss covered coniferous woods, they encounter a desperate young mountain tribal. He is searching for his beloved wife and his elder brother, both of whom he got separated from after an unsuccessful attempt to kill a cave bear. The last thing he saw was the cave bear in full pursuit of his wife. He could not help her as he had been knocked to the ground by the raging beast, and was struggling to regain full consciousness. The tribal will be clearly nervous and urges them to look for his wife during their travels. He will stay in his village a couple of miles to the north and pleads for assistance should they recover his wife, whether she be dead or alive.
On the next day of travel, they will journey upon a dim track in the forest and while they are preparing to ascend another path cut into the mountainside, they hear moans of lust from somewhere nearby. Upon closer inspection they will spy a young tribal woman in the heat of the act with an elder tribal male. They are consummating their forbidden love on the cold mountain moss, and beside them lay the skinned and slaughtered carcass of a huge bear.