I will be discussing them as part of the 99, if you want to build dedicated commander decks around them, you can also do that, but then their evaluations can shift dramatically both from them being built around completely and consistently available
The other three effects are a mix of effects that couldn't be done in just one of the colors
Fill your deck up with discard effects like Demand Answers, a few super-cheap artifacts like Tormod's Crypt, and then a ton of huge, game-winning effects: Portal to Phyrexia, Threefold Thunderhulk, Platinum Angel, Wurmcoil Engine, the works
Not only is making free copies of creatures a terrifying prospect, but the fact that Sin can provide multiple free lands is even scarier, as it provides the opponent with an amazing mana engine
Magic: The Gathering's Game Variant Explained Plane cards are special oversized cards that were first introduced in 2009 with the release of Planechase, a collection that contained 4 packs, each with a 60-card deck, 10 plane cards, and a special planar die