Mikey grew up in Littleton, Colorado playing his minor hockey with the Colorado Thunderbirds. He graduated to the USHL in 2013 debuting with the Fargo Force. Mikey was dealt from Fargo to the Sioux Falls Stampede during the 2014-15 season and went on to play a big role in helping the Stampede capture the Clark Cup, tying for the lead in playoff scoring.
He began his NCAA career the following season with the St. Cloud State Huskies of the NCHC. Mikey had a very good freshman season at St. Cloud State recording 33 points in 40 games while earning rookie of the month honors in January of 2016. He scored the game winning goal of the 2016 NCHC Tournament to help St. Cloud State win their first ever NCHC Tournament Championship. As a result of his strong play, the Los Angeles Kings selected Mikey in the 5th Round of the 2016 NHL Entry Draft. Mikey went on to play two more seasons of NCAA hockey before signing with the Kings at the conclusion of the 2017-18 season. He played three full seasons with the Ontario Reign of the AHL before signing with the Winnipeg Jets.
Mikey made his NHL debut for the Winnipeg Jets on April 11, 2021. He recorded his first NHL goal and point in November of the following season with in a win over the Carolina Hurricanes. He is currently a member of the Tampa Bay Lightning.