Because "Meteor Client 1.21.1 - 1.20.6 -- 1.16.5" is a high-volume search term, it attracts many fake websites. Here is the truth:

If you need cross-version compatibility without changing clients, Meteor is a solid choice—but don’t expect every feature to work identically across the entire version range. Crystal PvP, in particular, is severely degraded on anything older than 1.19.

The "Golden Age" version for many modpacks; requires older Java versions (typically Java 16 or 17).

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