Somewhere between ~15-75+ billion USD. Higher end if you want to include the hardware R&D/etc, which is arguably core to their metaverse concept. I love the idea that they don't even have a product _called_ metaverse. Most of the VR content developer acquisitions costs by Occulus Labs are undisclosed.

https://www.fool.com/investing/2024/04/01/meta-platforms-has... https://en.wikipedia.org/wiki/Reality_Labs#Acquisition_by_Fa... ~1.6 billion

World of Warcraft is the closest thing to the metaverse. But I'm biased since it's my favorite game (TBC, WoTLK, etc)