The nether reactor gives friendly mobs (players, tamed mobs, villagers, etc.) fire resistance, gives striders Speed III, and clears Wither I in a 64 block radius. It is activated using a complex structure shown on the next page.

In order to form a full reactor, you make the above multiblock structure, building from layer 1 upwards.

It is made using lots of valuables, including a nether star… good luck!
History
| 1.6.1 | * | Camel husks, nautili, and zombie nautili are now all affected by the nether reactor | |
|---|---|---|---|
| 1.5.2 | * | Camels, skeleton horses, zombie horses, and happy ghasts are now given fire resistance by the nether reactor, just like every other tamed mob | |
| 1.4.1 | * | The gobblerift, nether reactor, and soul seer now have emissive textures | |
| 1.4.0 | Release | * | The nether reactor core no longer requires gilded blackstone to craft, using normal blackstone instead |
| Release | - | Manic Compatibility Removed all Manic compatibility features. RIP. | |
| 1.1.0 | Beta 6 | * | The nether reactor can now be built with chiseled polished blackstone and raw gold blocks |
| 1.0.1 | + | We now have a small amount of compatibility with the Manic datapack. Most of this won’t make sense unless you’ve played with that datapack.
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| 0.3.0 | + | This isn’t the old nether reactor from the days of bedrock, as it has a completely different function. This nether reactor, made from blackstone, gilded blackstone, and netherite, gives all friendly mobs in a radius fire resistance, clears wither I from players, and gives striders speed III. The specifics can be found on its feature page. | |