This is a data pack/mod that adds naturally generating shrines dedicated to the all-powerful Wither. For obvious reasons, I recommend using a boss overhaul mod like Withering Heights to have the Wither's might be worthy of worship, you may also want to add some other mods like Biomes O' Plenty, Hearths, and the More Nether mod to make the Nether look more like how it appears in the screenshots.

Q&A

Q: Can I use this in my modpack?

A: Of course! This mod was meant for modpacks!

Q: Can I redistrubute this?

A: Unless you're in a third-world country, no.