Obsidian Reworked Add-on 1.21+

Obsidian has virtually no use in the vastness of Minecraft since nothing can be crafted from it. This is because Obsidian in the real world is quite brittle, though exceptionally hard. It's quite difficult to create anything from it. But the author of the mod Obsidian Reworked decided that Obsidian would become the perfect material for crafting new tools and armor.

The addon adds obsidian ingots, nuggets, gears, and new blocks while maintaining compatibility with other mods. The special Nether Guardian equipment is immune to fire.