The best replacement for necrons is tyranids.

The best alternatives to necrons are rated as following:
★★★★★  tyranids
★★★★★  tau
★★★★  chaos
★★★  space marines
★★★  orks
★★★  eldar
★★  reapers
★  grey knights
★  chaos daemons
★  imperial guard
★  daleks
★  space wolves
★  dark eldar
  tau tactics
  orcs
  nids
  tyranid
  eldar dark crusade

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

Other search terms related to necrons and their ratings are:
★★★★★ tau
★★★ tyranids
★ blood angels
eldar
You have in mind a companion for necrons and it is not yet here? Propose!



Google Trends

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necrons
tyranids
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