“ There is a place where there are living dinosaurs but in miniture.So there are foot long Tyranosaurus Rex's and four foot long Brontosauruses, for example.”
“ Temple of some malign being invites you warmly and offers help (curing,needed spell etc) for some minor sacrifice . Sacrifices must be everytime bigger to work - up to living inteligent creatures. Maybe you pay some other price,too...”
“ A city is being plagued by a swarm of winged mice. The vermin can get anywhere, and they can easily avoid their normal predators by simply flying away from them.”