Far to the north, past the cold, vast plains and tangles ancient forests, past even the brooding Deadfire Mountains, lies a real of ice and bitter cold. Barren and stark, few have ventured in to this icy realm. Hunting here is scarce and the wind seems to howl with the voices of demons. Yet there are rumors of a citadel in the heart of the ice field, rising above the wind-swept whiteness and glittering in the pale sunlight. Some say that the citadel was built of block of ice by giants. Others claim that some wild magic caused the structure to grow from the very ice. Yet others state in low voices that it is not ice that shines so, but a fortress of diamonds, built in ages past to guard the most powerful of magics in the world.
The players see a small shrine to the local nature deity just of the trail. Before they even approach it, they can smell the foul stench of rotting meat. If they inspect the shrine, they can see it has been desecrated by rotting organs in the last few days. There is no mistaking it for an obscure ritual, the organs are thrown everywhere, not left in specific places as in sacrifice.
If the players try to clean the shrine, they will soon find it has been boobytrapped to fling sharp splinters covered in the rotting gore in every direction. While only doing a few points of damage, they injured players will likely take sick soon unless they get medical attention.