2012-13: In this fourth season with the Thunderbirds Elliot played in 63 games and had two goals and two assists with 147 penalty minutes. He played in all seven playoff games against the Kelowna Rockets but did not register a point. He had 13 penalty minutes in the playoffs.
2011-12: In his third season with the T-Birds, Elliot played in 65 games and had five points on two goals and three assists. He put the T-Birds ahead of the Lethbridge Hurricanes on November 9 when he scored at 12:17 of the third period, which led to a 3-2 win for Seattle.
2010-11: Elliot finished his second season with five goals and eight assists for 13 points in 72 games. He also had 118 penalty minutes. On October 9 at Prospera Centre in Chilliwack he had a Gordie How hat trick with a goal, assist and fight against the Bruins. Elliot attended the Washington Capitals Development Camp in June.
2009-10: Mitch played 56 games with the Thunderbirds ending the season with one goal and three assists for four points and 39 penalty minutes. He scored his first career WHL goal at Kamloops on February 19.
2008-09: Mitch played in 30 games with the Caribou Cougars of the BCMML this season. He had two goals and two assists for four points. Mitch also had 26 penalty minutes.