“ There are no scrolls in this world, but there are crystals of various sizes, colors and qualities. Every spell has a requirement on the amount and characteristics of crystals that must be held in order for the spell to be cast, crystals which would shatter should the cast be successful. Now picture a land where crystals are scarce except for high concentrations of them in specific spots throughout the land. A number of scenarios could occur, such as benign companies selling the mined valuable for cheap, a region in constant magic-intense war zone, an area of crystals in the quicksand, or an undiscovered patch next to a town...”
“ (Post zombie apocalypse)-a tribe of humans
Culture: Drumming circles daily around an arena for their bravest brutes to slaughter their accepted foe, the zombie. Feasts of overcooked zombie flesh (to kill all of the zombie virus present). Wooden fortress that make this tribe in the far future look several millennium behind in technology. Instead of becoming a troublesome and unnatural foe that they seek to cure, this tribe has accepted that Zombies will continue to roam their land and, if the undead were to perish (be cured), this tribe would suffer as well.”
“ 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.”