Machines and materials chart by SparxxUI rates accurate for 2.4.1 At T13, guaranteed to drop 3 organs at once. The drop rate of the ingredients scales with difficulty: one organ at T1, with a chance to drop the second one at higher difficulties, and even two guaranteed at T7, with a chance of third one. Nobody promised it will be easy, as you need to fight them two at a time (except for the Realm of Fright). On level 60, each machine opens a different portal, on level 70, there is a separate machine depending on which set of Uber bosses you wish to fight. On level 60, you need three devices, on level 70, you will require four, and they must all be of different types.

Note that none of the devices are guaranteed to drop until Torment IV, and level 60 and 70 keys are not interchangeable.

From those, you will obtain a set of Infernal Machines.

Most likely, you will need to do it more than once.

On Torment I difficulty or higher, kill the four Keywardens: Odeg, Sokahr, Xah'Rith and Nekarat.

Make sure to level up the Jeweler (level 10 and 12 respectively).

Purchase a Plan from Squirt the Peddler (2 million for the level 60 plan, which includes all four variants, or 5 million for the level 70 plan).

To make a Hellfire Ring, the following steps need to be completed:

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