>>2180
As posters noted above those are users posting via Tor or Lokinet. They don't get IDs or IP hashes, they are all count as 1 poster (on the whole site) and they aren't included the number of posters on the board page.
BOs can disallow the use of Tor on their board, that option was included in case of certain attacks. I encourage you not to choose using it, unless it's absolutely necessary.