The best replacement for hydra is vega.

The best alternatives to hydra are rated as following:
★★★★★  vega
★★★★★  bt
★★★★★  dragon
★★★★  bloodthirster riven
★★★★  cigar oasis
★★★★  coral
★★★★  mobzilla
★★★  hydra 52
★★★  bloodthirster
★★★  photomatix
★★★  hercules
★★★  botrk
★★★  hydro
★★  megasquirt
★★  aim
★★  rybka
★★  aegina
★★  medusa
★★  stalker
★★  adams
★  botrk zed
★  sol
★  obelia
★  cerberus
★  zuni
★  mutant zombie
★  roach
★  fire coral
★  shredder
  muta
  bloodthirster lee sin
  ender dragon
  maxspect razor
  daphnia
  m3 resident evil
  stem
  wither

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

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



Google Trends

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hydra
vega
bt