[{_id:1,traits:{Rarity:{infoin:15,},Type:{iron:3,sliver:5,wood:7,},},},{_id:2,traits:{Cloth:{barron1:11,barron2:12,},Hair:{black:6,yellow:9,red:8}},}]

db.collection.aggregate([{"$project":{"traits":{"$reduce":{"input":{"$objectToArray":{"$getField":{"field":"v","input":{"$first":{"$objectToArray":"$traits"}}}}},"initialValue":0,"in":{"$sum":["$$value","$$this.v"]}}}}}])