“ Mining in a certain area turns all exposed skin (maybe just parts that are actively disturbing the chemicals that cause the reaction) of the those doing the mining to a dark blue color. Will wear off taking as many years/days spent in the mine. ... meeting a party of blue-skinned humans armed with pick-axes etc. Strange disease? Demon offspring? Curse? If they meet only one ex-worker, they will very carefully listen to any stories he says, no matter if drunken or insane, or just makes up to get a beer.”
“ The player characters, experienced and somewhat well known, hear rumors and travelers' tales about a distant area being overrun by dragons (or other terrifying monstrosities). The locals have sent them a message, begging for heroic aid.
When they investigate, they discover that nothing of the sort is going on. It turns out that a group of thieves wanted them out of the way so that they could rob them (or someone who would normally receive their protection).”
“ These little beetles have heads at both ends of their bodies. This allows them to feed on leaves at twice the rate of their normal cousins, causing great damage to crops. They look like ladybugs more than actual beetles, but have no wings. They have a funny way of moving if one stops to watch them, as both heads seem to vie for picking the direction at any given time. Their favorite nourishment is sugar cane. After feasting on these for some time, they develop short bursts of frenetic energy, and can be seen racing back and forth without purpose, which looks quite comical to onlookers. They are otherwise normal bugs. Of course the pc's might not know that.”