The best replacement for tf2 is cod.

The best alternatives to tf2 are rated as following:
★★★★★  cod
★★★  minecraft
★★★  ponyville
★★  loadout
★★  cs go
★★  css
★★  tfc
★★  final combat
★  fortress forever
★  mnc
★  monday night combat
★  planetside 2
★  l4d
★  l4d2
★  equestria
  dota 2
  battlefield heroes
  mlp
  combat arms
  bfh
  hl2

Your alternative for tf2 is not listed? Suggest!
Speaking about tf2, one probably shouldn't forget about controller.

Other search terms related to tf2 and their ratings are:
★★★★★ controller
★ gmod
You have in mind a companion for tf2 and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of tf2 in all years. Click on graph for more.
tf2
cod
minecraft