He most recently faced Brett Rogers, losing via a "contentious" unanimous decision. He next faced former King of the Cage champion Tony Lopez, losing via submission due to punches in the second round.
He next faced Rob Jackson, losing via split decision. He then went on to face Dave Huckaba in his Shark Fights debut, losing via unanimous decision. Afterwards, Warpath faced Carter Williams, losing via technical knockout thirteen seconds into the bout to bring his record to a disappointing but telling 19-23-3.
Villareal next fought a rematch against a formerly-retired Don Frye, defeating Frye in a vicious but sad first round knockout.
- Don Frye vs. Ruben Villareal Number 1 - The fight was for King of the Cage. Don Frye and Ruben Villareal fought to a draw. Don Frye called it 'the Little Big Horn and the Seventh Cavalry.'
- Antonio Silva vs. Ruben Villareal
- Bas Rutten vs. Ruben Villareal - Bas Rutten came out of retirement specially for the bout before returning to it. Villareal replaced Kimo Leopoldo on extremely short notice after Leopoldo tested positive.
- Ruben Villareal vs. Don Frye 2 - Don Frye came out of retirement for the rematch of the 2006 fight, in 2011.