Released originally around May 2014, Update 10.1 was a critical patch for the game’s transition to a functional offline experience. Key features included:
Resolved common issues where the game would freeze when switching between Single-Player and Multiplayer modes. simcity update101 17 dlcrepackrgmechanics best
You can build cities locally on your machine without needing a constant internet connection. Performance Fixes: Released originally around May 2014, Update 10
For those interested in RG (Region) mechanics, here's a brief overview: Released originally around May 2014