It's useful as a quick way of pressuring someone early or you can use it to hit hard later with a game-winning number of Zombies and life
There arent many useful ways to remove permanents from play using utility lands, but Blast Zone is definitely the best of them
If you do, reveal cards from the top of your library until you reveal a creature card, put that card onto the battlefield, then shuffle all other cards revealed this way into your library
Of course, it would have been hard to do this date and retain Cloud's consistent pose, so I get why it wasn't included
Theres an argument that these are better in the 99 than as the commanders of a dragon deck because they offer card advantage when they ETB and fetch the other one from your library
It seems less good because Raise Dead, Disfigure and pay a life for a card are all one mana abilities and because they cover less of a range than the other Confluences