Sinister key

Sinister Key is a members-only item on the OSRS Grand Exchange in the other category.

In-game examine text: "You get a sense of dread from this key."

It has a Grand Exchange buy limit of 11,000 every four hours, a high alchemy value of 48 gp, and item ID 993.

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Sinister Key shows an active flip setup with a margin of +456 gp and 7,075 trades over the last 24 hours.

At the buy limit of 11,000 every four hours, max profit per cycle is about 5.02m gp — high margin with healthy liquidity.