The best replacement for source engine is unreal engine.

The best alternatives to source engine are rated as following:
★★★★★  unreal engine
★★★  udk
★  cryengine 2
  unreal 3

Your alternative for source engine is not listed? Suggest!


No companions for source engine have been suggested so far.
You have in mind a companion for source engine and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of source engine in all years. Click on graph for more.
source engine
unreal engine
udk