[{_id:"1",name:"abc123",colors:[1,2,3]},{_id:"2",name:"def431",colors:[4,2,1]},{_id:"3",name:"htl534",colors:[3,5,7]},{_id:"4",name:"lwq154",colors:[9,1,4]}]

db.collection.aggregate([{"$group":{"_id":null,"result":{"$push":"$name"}}}])