In 2016, Mary joined the Marble League as part of Team Primary, further competing with the team in Marble League 2017, winning a gold medal during the Funnel Race whilst competing in the latter. In Marble League 2018, Mary and her brother Prim participated as a part of Team Momary, along with Mo, Momo, and Mimo.
Mary, along with the rest of Team Primary, failed to qualify for Marble League 2019, and as such participated in the Marble League Showdown 2019. Team Primary placed fourth, qualifying for the Marble League 2020 Qualifiers with 36 points overall.
Mary and Prim were sent as representatives for Team Primary for the Marbula One 2020 season. Mary performed disastrously, finishing 16th in 3 races and only getting 15th in one race due to Wospy's incident. failing to score a single point for the season. Because of this, she has become a meme among the fans, with many comparing her to a cube.
While the team may have experienced some success in Marbula One, the team could not show it in the Marble League 2020 Qualifiers - as the team failed to qualify for the third consecutive year. Ironically, Mary's participation in the Funnel Endurance event could not match her past performances, as she performed very poorly. She later resigned as captain of Team Primary.
|Marble League 2016||Balancing||Team||15th||208 cm||0|
|Relay Race||Team||13th||24.60 sec.||1|
|Collision||Team||3rd||Consolation Round Winners||5|
|Sand Rally||Individual||9th||58.58 sec.||0|
|Team Pursuit||Team||12th||26.17 sec.||0|
|Precision Slalom||Team||15th||7 pts||0|
|Quartet Diving||Team||12th||28.69 pts||0|
|Marble League 2017 Qualifiers||Relay Race||Team||2nd||9.92 sec.||12|
|Block Pushing||Team||3rd||65.6 cm||10|
|Marble League 2017||Funnel Race||Individual||1st||1:44.51||25|
|Fidget Spinner Collision||Team||3rd||3rd Place Winners||15|
|Block Pushing||Team||14th||124.0 cm||2|
|High Jump||Individual||12th||36 cm||4|
|Marble League 2018 Qualifiers||Curling||Team||1st||Winners||8|
|5 Meter Ice Dash||Individual||5th||5.02 sec.||4|
|Marble League 2018||Team Pursuit||Team||8th||32.20 sec.||8|
|Snowboard Cross||Individual||13th||53.90 sec.||5|
|Ice Hockey||Team||8th||Quarterfinal Loss||8|
|Amazing Maze Marble Race 2018||Maze||Team||10th||Heat Loss||-|
|Marble League 2019 Qualifiers||Block Pushing||Team||16th||91.5 cm||3|
|Marble League Showdown 2019||Collision||Team||4th||3rd Place Losers||9|
|Marbula One Season 1||O'raceway Grand Prix||Individual||15th||5:35.71||0|
|Hivedrive Grand Prix||Individual||16th||+1 lap||0|
|Greenstone Grand Prix||Individual||16th||6:14.61||0|
|Razzway Grand Prix||Individual||16th||5:44.81||0|
|Marble League 2020 Qualifiers||Balancing||Team||12th||308 cm||8|
|Block Pushing||Team||3rd||68.5 cm||18|
|Marble League Showdown 2020||Relay Run||Team||2nd||8.854 sec.||15|
- She was the winner of Team Primary's only individual gold medal to date - their victory in the Funnel Race.