Is it understood that you can play this land as your 1 land drop per turn OR for its Login cost? Or do I need to include that in the reminder text? This is already getting wordy and I'm not sure the rules baggage is worth it.

I want there to only ever be one field on the battlefield at any given time. That detail is very important for the design I'm working on, but is there a way to make this overall more simple?

Hmm. It's pretty difficult to make a frame for lands that have colour but that are still understood to be lands at all. The land frame is pretty much the biggest cue to something being playable as a land drop, so I wonder whether this could lose the blue colour indicator and just have the land frame. At the moment it really isn't obvious-at-a-glance that this is playable as a land.

So Field works very similarly to World? Seems like it could just be World to me. At the moment this reminder text actually does leave a little while between the new Field arriving and the old one leaving - people can respond to the triggered ability. You could use a replacement effect, but I think SBAs are a more sensible way to achieve that, except that it's good not to add new SBAs if existing ones will serve your purpose.

> 704.5m If two or more permanents have the supertype world, all except the one that has been a permanent with the world supertype on the battlefield for the shortest amount of time are put into their owners' graveyards. In the event of a tie for the shortest amount of time, all are put into their owners' graveyards. This is called the "world rule."

"Lands" that don't LOOK like lands need to look like lands.

Multiverses simple frames can't do that - but not having a mana cost is a big step in the right direction (looking at YOU misplayable mana artifacts)

On t'other hand - hyper-legendary? Enchant-World-lands? Gibber.

(V's referring to Mistvein Borderpost and friends, which technically aren't lands at all and don't look like them in your hand, but do work exactly as if they were lands. They're confusing for the same kind of reason that this card having a blue frame is.)

I took a step back and looked at the card for a day and decided I was trying to do too much. So I went ahead and simplified. The Login ability is gone so you just play it like a land and the card entering the battlefield now triggers all other Fields to be put on the bottom of their owner's decks.

The whole point to my Field idea is another way for lands to produce colored mana, not come into play tapped and have an extra, yet powerful ability. But to balance those abilities, your opponent always gets to take advantage of them before you do. Sound good?

In theory, I'd say the card is balanced, since your opponent can play a field, and 'destroy your land' in the process. That seems like a bug, though, not a feature.

I like 'world' permanents, and think that Magic still has a place for them. That said, I think that space is filled with very goofy, splashy cards, or cards that mitigate the draw back with a feature (for example, a world permanent that enters the battlefield and immediately draws you two cards). This is a very powerful land, with a drawback that will make you want to stop playing Magic altogether when it happens.

My suggestion would be to work Fields the way the Legend rule works right now. Add "...put all other Fields under your control on the bottom..." (I should point out, that probably makes this card too good. Free Howling Mine seems powerful.) Or find a different way to make the drawback, not quite a drawback (for example, when a new field enters play, replace this card with a tapped basic Island from your library.) The alternative would be one of two options in the real world: 1). The card wouldn't be powerful enough for Standard, is not considered worth the pain by most casual players, and gets relegated to the bargain bin, or 2). The card is good enough for Standard, and aggro decks start packing 10x Fields as a form of round 1 Strip Mine, regardless of ability.