The best replacement for civ 5 is civ 4.

The best alternatives to civ 5 are rated as following:
★★★★★  civ 4
★★★★  total war
★★★  eu4
★★★  starcraft 2
★★  civ 3
★★  rome 2
★★  age of empires
★★  europa universalis 4
★  ck2
★  xcom
★  civ 2
★  shogun 2
★  empire total war
★  civ rev
★  age of empires 3
★  civ revolution
★  rome total war
★  crusader kings 2
  total war rome 2
  mafia 2
  age of wonders 3
  civ iv

Your alternative for civ 5 is not listed? Suggest!
Speaking about civ 5, one probably shouldn't forget about hamachi.

Other search terms related to civ 5 and their ratings are:
★★★★★ hamachi
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