Mana Maze is a Blue Enchantment that works as an effective stax piece. Having had Chris play this card against me several times, I can confirm it is effective. This underplayed stax piece can also be used offensively making it the Card of the Week.
The oracle text can be found here.
The way that Mana Maze is worded makes it fairly unique among stax pieces. This is because it does not affect each player, like other pieces such as Deafening Silence. It effects everyone at the table, resetting at the beginning of each turn. For example, if it is my turn and during my upkeep Chris casts a Brainstorm. This means that no-one can cast a blue spell, or a spell with Blue in it. Until either a spell of a different colour is cast, or the start of the next turn. This can completely hose your opponents if they are playing a mono coloured deck, or at least force them to play around it. If you are playing a control deck it will allow you to make good use of counter spells. All the time ensuring that your counterspells won’t get countered.
The downside of Mana Maze is that it affects you as well. This means you are just as vulnerable to players casting spells in your upkeep as your opponents. Additionally much like other stax pieces this one draws the ire of your opponents. It becomes central to the game and your opponents will want to get rid of it.
Mana Maze is best in decks that are primarily colourless and this provides a loophole, for example Urza, Lord high Artificer. It also works really well in Golos, Tireless Pilgrim decks as once Golos is out they are looking to spin the wheel instead of casting spell. As well as working in stax decks such as Grand Arbiter Augustin IV, or Oloro, Ageless Ascetic.