Colonies is also cross platform with the PC version, if you'll want to add to that.
You're absolutely correct. It's one of the progenitors of cross-platform play :)
EDIT:
If you're in the market for LP1, make sure to get the Colonies Edition. CE includes all previous DLCs, new game modes, the aforementioned PC cross-platform play, and more. Online player base is likely going to be stronger on the CE version today. (and no, vanilla is not multiplayer compatible with CE since it uses a different TitleID)
The wiki below nicely summarizes the differences between LP1 vanilla and Colonies Edition.:
https://lostplanet.fandom.com/wiki/Lost_Planet:_Extreme_Condition_Colonies_Edition
Colonies Edition:
https://www.microsoft.com/en-us/p/lost-planet-colonies/c39lxt2j8ltf
https://marketplace.xbox.com/en-US/Product/LOST-PLANET-COLONIES/66acd000-77fe-1000-9115-d802434307de
EDIT 2:
Perfect excuse for launching super nova again :)
Last edited: