The best replacement for unreal is unity.

The best alternatives to unreal are rated as following:
★★★★★  unity
★★★★★  quake
★★★  cryengine
★★★  source
★  udk
★  surreal
★  frostbite
★  xna
★  quake 2
★  unity3d
  unity engine
  past unreal
  havok
  source engine
  crytek

Your alternative for unreal is not listed? Suggest!
Speaking about unreal, one probably shouldn't forget about anope.

Other search terms related to unreal and their ratings are:
★★★★★ anope
★★★ wwise
You have in mind a companion for unreal and it is not yet here? Propose!



Google Trends

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unreal
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