I didn't see this posted here so i'm going to shed a light on it. DarkFlameUniverse: a fully implemented server for NetDevil's 2010 MMO Lego Universe. [AGPL 3.0] : r/opensourcegames
GitHub - cuzitsjonny/JALUS: A PoC of a LEGO Universe server emulator; Written in C++; Discontinued
LEGO Universe emu Darkflame Universe has released its server source code | Massively Overpowered
55000 LEGO Universe | Brickipedia | Fandom
Lego Universe - Wikipedia
Play LEGO Star Wars: The Complete Saga on NDS - Emulator Online