Database
[{"_id":ObjectId("60bea750c26a1c7095387d00"),"rounds":[{"round_number":"0","round_values":{"max_player_pot":"0.25","pot_multiple":"0.625",}},{"round_number":"1","round_values":{"max_player_pot":"0.0","pot_multiple":"0.0",}}],"GameID":"392124717","ComputerName":"awdfadf",}]
Query
db.collection.aggregate([{$unwind:"$rounds"},{$replaceRoot:{newRoot:{$mergeObjects:[{GameID:"$GameID",ComputerName:"$ComputerName"},"$rounds.round_values"]}}}])