If this is the first article on this subject you are reading today, I would direct you to first read Matt Tabak's much more comprehensive version of the rules updates here, first. While Matt is covering that "What" of what will be changing in total (including the more rules-driven changes), I will be covering the just the "Why" of the legendary and Planeswalker uniqueness rules, and what brought us to make those changes from a design and development perspective.
Dissecting the Changes
As Matt mentioned in his article, beginning with Magic 2014 Core Set, we are changing how the game handles several things, including legendary and Planeswalker uniqueness. The new rule separates the field of play into your battlefield and your opponent's battlefield, and only checks those to make sure that there are not multiple copies of one legend with the same name or Planeswalker with the same type. When multiple copies are on the battlefield under one player's control, that player chooses one to put into the graveyard as a state-based effect until only one remains. You will still only be allowed to have one version or copy of Jace or Geist of Saint Traft on the battlefield at one time, but your opponent will be allowed to have one as well. If you play a second, or one comes into play under your control for another reason (such as an Oblivion Ring leaving play), you will choose which one you wish to retain. This will allow you to somewhat mitigate the downside of drawing a second copy of a Planeswalker by playing that copy to, in effect, refresh the loyalty of a Planeswalker or to get a second enters-the-battlefield trigger on a legendary permanent.
I believe that the net result of the change is that the game has more meaningful and satisfying interactions. While it was useful to use the "legend rule" and clones to kill your opponent's hard-to-target legends, or to play your Planeswalker to kill your opponent's, the general feeling within the Pit was that this interaction was not how we wanted games to be decided. I don't feel that the old version of the rules was inherently bad, but it did end up making interactions between players who shared legendary permanents a game about who could use his or her permanent as a terror more often and not about the cool things the legendary permanents or Planeswalkers themselves could do. In the new version of the rules, a player is still disadvantaged for drawing too many of a Planeswalker or legend, but he or she just has some tools to be able to mitigate it.
Why These Changes Were Made
There are many reasons the change to the rules is coming about now. The first, along with any change we make to the Comprehensive Rules, is that we believe it provides a better overall game-play experience to our players. The second is that as we print more Planeswalkers, we learn more about them and how they work, and how to better balance them and make them fun. We found that games where players used their Planeswalkers to continuously nullify each other weren't particularly interesting, and overall it made Planeswalkers less fun as a result. The third reason is that we simply print more legends today than we used to, both because they give us opportunities to tell the story of Magic on cards, and because they afford us the ability to grant powers and abilities to cards that we might not want players to have multiple copies of at the same time.
This isn't the first time we have changed the legendary rule. The original rule was that the first legend to come into play trumped all others. This was changed in Champions of Kamigawa to the nullification rule that we have played with since. The version in Champions of Kamigawa greatly improved how legendary permanents played when compared to the original version—I can't imagine how that block would've played without that change—but it wasn't perfect. A key part to the success of iteration is to not stop just because things are working pretty well. It's important to constantly talk about what is working and what is not, and eventually those discussions came back to the legendary rule. As the rest of the game improved over time, it ended up being below what we wanted for the best game play possible. We believe the new rule is an improvement that will allow players to feel more confident running legendary permanents in their decks, and allow for games based around more normal interactions when each player has the legend out, rather than having games devolve into players "legend ruling" each other turn after turn.
The Planeswalker uniqueness rule is a bit more complex, if only because it is a much younger rule than the legendary rule. As I mentioned before, Planeswalkers have become more and more important to our game since their introduction in Lorwyn nearly five years ago. We have always used legendary creatures to tell the story of the people and creatures of the planes we visit, but increasingly use Planeswalkers to tell the more epic story between planes and over multiple years. This continued canon, of course, leads to us making new versions of most Planeswalkers every few years. Jace is currently on his fourth iteration. Garruk, Liliana, Ajani, and Chandra have each seen their third versions. We have two versions of Sorin, Elspeth, Gideon, and Tezzeret. These numbers will simply go up over time, and we will begin to find that as the characters and their cards change, they will start to overlap in more and more decks. While running all of the versions of Liliana in your deck will still not be optimal, you will no longer be punished when you decided to run the four-mana version and your opponent was able to stick the three-mana version first. This problem was over-exaggerated by the fact that Planeswalkers are able to use their abilities the turn you cast them, and it gave a tremendous advantage to the player who was able to play his or her Planeswalker first. Under the new rule, you will also be able to tick a Planeswalker down on one turn, then play another copy and use the abilities of that Planeswalker again. This should help mitigate the problems with drawing multiple copies of the same Planeswalker.
We will continue to add several new Planeswalkers per year to our lineup, but we also anticipate returning to our core "Lorwyn 5" frequently. Being able to keep excitement about them high rather than continuously making their cards worse over time by creating overlaps is definitely a goal for us.
I would like to reiterate that these changes were only made after much discussion and playtesting within R&D. We spent a good deal of time in meeting rooms and around playtesting tables trying it out, discussing whether these changes should be made at all, and the exact ways in which the changes could occur. We playtested several variations of both the new legendary rule and the Planeswalker uniqueness rule to ensure we were choosing the ones that improve game play the most.
We have been playing internally with these changes for almost a year now, and I can say with confidence as a player that I believe they are an overall improvement to my enjoyment of Magic. Because this change has been in the pipeline for almost a year, legends and Planeswalkers moving forward have been developed with this rule in mind and tested with a copy on either side of the board to make sure the game play is still fun. We are cognizant of what these changes mean for how we balance legends and Planeswalkers in the future, and we have taken them into account when costing them and their abilities.
More than just retaining the importance of Planeswalkers and legends for story reasons, R&D is excited about this change, as it opens up a lot of design space that was previously off limits due to Planeswalkers and legends gaining prominence in our game. Until this change, we were unwilling to print cards like Faith's Fetters that prevented a permanent from activating abilities instead of exiling it outright. This was due to the fact that casting Faith's Fetters on a Planeswalker would not only take it out of the game, but also another version that player had in his or her hand. It is also highly likely that without this change, we would've just stopped making as many powerful Clones as we have in the past because of the pressure they put on legendary creatures.
This change will also let us create legendary lands again, a process that (outside of Eye of Ugin) hasn't really been seen since the Kamigawa block, and for good reason. Most players found their game play under the old legend rule to be not particularly fun. Between both getting your land destroyed in a fashion you can't respond to by an opponent and having a dead card in your hand if you happened to draw two copies, they were a bad sell. While I don't anticipate we will do them very often, it is another tool we have for balancing powerful lands going forward.
Integrating with History
While I believe these rules are overall an improvement in Magic, we have been designing cards for the past nineteen years with other versions of the legendary rule in mind, and this will naturally cause some cards to behave differently than they were originally designed. For some cards, this will make them more powerful; for others, less powerful. The most notable change for Modern, Legacy, Vintage, and Commander will be that legendary lands will be much more attractive to run in decks. While they still suffer from the drawback of not being able to have more than one in play if you draw multiples, it does make it much easier for decks to run singleton or even a few copies of powerful legendary permanents such as Gaea's Cradle, Karakas, Academy Ruins, or Mox Opal. We will keep a close lookout for the power of these lands in Modern, Legacy, and Vintage, and trust that Commander Rules Committee (who have been previously informed of this change) will keep a lookout for the power level in that format, as well as the power level of commanders that are traditionally difficult to deal with, such as Uril, the Miststalker. It is not currently expected that these rules changes will bring about any changes to the Modern, Legacy, or Vintage Banned and Restricted lists, but we will be keeping a close eye on the formats between the release of Magic 2014 Core Set and Theros, and we will make any changes if they are deemed necessary.
I know that, with any change we announce, we receive a lot of feedback—some positive and some negative. We are more than willing to hear any thoughts all of you have on these changes, and any other changes that happen in the future. We will try to respond to concerns, but we will likely not be able to do it on an individual basis because of the volume. I hope that you trust that these changes will make the game more fun as a whole, and that we will use the additional design space in good ways to make more fun and interesting cards, which will lead to better games of Magic. I look forward to Theros and beyond, and to revealing some of the interesting things this change has allowed us to do.