Which engine was used for Arena? Edit

Does anyone know what engine was used for Arena? I saw some guesses that it was Doom, and indeed it seems to have come out slightly after Doom was released (but not so soon that it would be impossible for it to have licensed the Doom engine), however, I have not seen anything that sounds like convincing proof that it used the Doom engine. Jondice0 (talk) 22:08, December 25, 2016 (UTC)Jondice0Jondice0 (talk) 22:08, December 25, 2016 (UTC)