Fiendish ashes

Fiendish Ashes is a free-to-play item on the OSRS Grand Exchange in the other category.

In-game examine text: "A heap of ashes."

It has a Grand Exchange buy limit of 3,000 every four hours, a high alchemy value of 1 gp, and item ID 25766.

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Fiendish Ashes shows an active flip setup with a margin of +4 gp and 5,737 trades over the last 24 hours.

At the buy limit of 3,000 every four hours, max profit per cycle is about 12.0k gp — high margin with healthy liquidity.