uSurvival is the world's simplest and easiest-to-use player multiplayer survival engine for one reason: 99% of player multiplayer projects fail because they are too complex.
uSurvival uses mirrored networking. With Mirror, the server and client are a single project and share 95% of the code. (hence the name "Mirror"). Thanks to Mirror, uMMORPG requires less than 10,000 lines of code and can still easily scale to 500-1000 CCUs.