“ When was the last time a character caught a cold or flu? Real people get them every now and again even with solid heating and dry interiors. Your characters are out in the cold and wet, and even inside is not always dry and warm. Imagine having to stop your dungeon crawl, sitting in a tight defensive position, while you all are feverish.”
“ A wizard has cast a slow action freezing spell upon a PC. The air gets colder around the PC by one degree a day. If the spell is not broken within a few weeks the PC will freeze and die.”
“ The air had grown chill the minute they descended into the strange valley, which was unmarked on any of their maps. It was so strange here, devoid of animal life and completely silent. The horses were nervous the entire journey through the vale. As they set about to collect firewood for the campfire they could hear their own voices as dim echoes through the eerie silence.
The food didn't taste anything that evening and their sleep was cold and troubled by nightmares. While they are clearing camp the next morning, one of them stumbles over a piece of stone jutting out of the ground nearby the horses. On closer inspection there seems to be runes engraved into the polished surface. The symbols true meaning is no more known among mere mortals and if they decide to dig deeper, they will discover that it is an ancient altar buried within the soil.
Any historically oriented party member will recognize the largest symbol to be the insignia of the powerful warlock who ruled this realm several centuries ago. At their departure from the area, something will seem amiss with one of the party members and all will remember the stories of the warlock's thousand curses.”