Play Hidden Oxygen Online Game. One of many Educational Games to play online on your web browser for free at KBH Games. Hidden Oxygen is made using Unity technology. Tagged as Educational Games, Logic Games, Puzzle Games, and Sudoku Games. Hidden Oxygen Game App is also available for your Android device on the GooglePlay Store. Upvoted by 14 players. Other games you might like are Hidden Objects: Dragon Land and Hidden Cats. No download or installation needed to play this free game. Hope this game brings a little joy into your daily life.