Lantadyme

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

In-game examine text: "A powerful herb."

It has a Grand Exchange buy limit of 11,000 every four hours, a high alchemy value of 40 gp, and item ID 2481.

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Lantadyme shows an active flip setup with a margin of +37 gp and 345,047 trades over the last 24 hours.

At the buy limit of 11,000 every four hours, max profit per cycle is about 407.0k gp — high margin with healthy liquidity.