William 66 has seen 25 bands.

Band Concerts Seen
  Acid Reign 1 concert
  Akercocke 1 concert
  Alexisonfire 1 concert
  Anthrax 1 concert
  BABYMETAL 1 concert
  Behemoth 1 concert
  Bring Me The Horizon 1 concert
  Evil Scarecrow 1 concert
  Foetal Juice 1 concert
  Ghost Bath 1 concert
  Gojira 1 concert
  Marmozets 1 concert
  Mastodon 1 concert
  Metallica 1 concert
  Modestep 1 concert
  Pierce the Veil 1 concert
  Rotting Christ 1 concert
  Royal Blood 1 concert
  Satyricon 1 concert
  Slayer 1 concert
  The Wombats 1 concert
  Twin Atlantic 1 concert
  Twisted Sister 1 concert
  Vallenfyre 1 concert
  Venom 1 concert