Endless Horizons

Pretty awesome as long as it doesn't get destroyed. Card advantage is rare in mono white decks, and this card helps making each of your cards count by thinning your library of Plains. That way, you can either choose to get a land, or get a card from your deck that will most surely not be a land, and instead be something you can use to beat your opponent with.

Still, you should probably be careful of removing all of your Plains at once with a single Endless Horizons because of the risk of the enchantment being destroyed, leaving you without enough mana for the rest of the game. Well, that is, unless you've already got the mana you need out of your deck - in that case you might as well remove all of the excess Plains that you'd rather avoid.
Endless Horizons also seem like a good option for decks that run global land destruction such as Armageddon. Destroying all lands while ensuring yourself access to your own lands seem like a neat strategy.

One thing no one has mentioned yet is the fact that this is the best way of clearing your deck of land for top decking. The worst way to loose is to draw a land when anything else would do. Not a 5 star card by any means, because like someone said earlier you don't want to have more than 3 in a deck and there is a right time and a wrong time to play this card. Play it when you dont need land or your trying to hard cast (pay the total converted mana cost) an expensive spell.

I give it 4 stars. We have house games which are far more relaxed than tournament play. This card is wonderful for trying to get new players to easily understand.

of course the first one of these is that you draw is great. but it only works in a mostly white deck, and every one past the first is not useful at all. which relegates it to a 2 or 3 of, which means drawing them at the exact right time is a little hard...still not bad, i just don't like it a lot.

seems to be a good card to make sure u dont get landlocked...but i can see alot of people screwing themselves over...u this as soon as u have 4 mana...remove all ur lands from the game,someone destroys the enchantment...ur pretty much done,worse if they destroy the lands u have left....id only use this late game

The conditions under which this card will actually benefit you are so far-fetched and unlikely that if you have this card in your deck, you might as well save yourself some time and just forfeit the game.