One of the things I found interesting while playing the game is that it's kind of like a series of logic puzzles. Each room you get to, you've got a logic puzzle. You work out what to do, and then you can move onto the next one.

I don't know if you saw Jonathan Smith's talk about the springy path, so you could get through the game and generally get through the game without too much resistance, but you can see all these other things if you go back and look again.

But the bit about being in a room and trying to work out what to do in a room kind of reminds me of point-and-click adventures. It's something that's been kind of left by the wayside, that way of doing things. Obviously, it's in no way a point-and-click adventure, but that active process that you go through as a player is similar.

It's one of those games where one person might get it straight away. They'll walk into a room and go, "Okay, I get it." And then someone else will be there for an hour. I've seen that with your game. Some people do it straight away, and some people take forever. How on earth do you balance something like that? It depends on the minds approaching the game in a much more exaggerated way than in most games.

JB: Early on, once I had all these ideas and was really hyped about the game, I decided that this is going to be the best game I've done so far. It's going to be like a philosophical pursuit for me. So I'm going to abandon all the other traditional ideas about game design that I've had.

Those include stuff like, "You need to have danger in order to keep the player interested." It started as an action-platformer, and it moved to puzzles when it was like, "Well, I don't want to kill the player or have lives, so how do I make the game interesting?" It's about thinking about where you are, and not just jumping over monsters.

Another part of game design that I just threw out was the idea of balance, or even the idea that everybody should be able to finish a game. That's certainly something that's come into prevalence. It's not something the industry does very well. People still don't play through most games.

But it's something that designers try to do. I was like, "No." This game is like a meditation or a kind of study -- a fun kind of study, hopefully. But it's about understanding the answers to these puzzles, and if you don't understand them yet, you just haven't finished the game, and that's okay.

Now, I did design the game because... not only are different people going to have different ease at solving this kind of puzzle, based on how much they've thought about weird time stuff or if they've read science fiction as a kid. I don't know what it has to do with. Not only that, but different people find different puzzles harder than others. There are definitely some puzzles that are easier and some that are harder, but among the ones that are harder, you just don't know.

So the game is designed so that it doesn't actually block you in a room almost ever. It does that a very little bit at the beginning in order to make sure the player understands the rules of the game. It starts out with just rewind, and then rewind with exceptions, but once you understand the exceptions... well, you can get through that level without really understanding it by failing, but once it's been shown to you, then the game is actually open. All you have to do is walk to the end of every level. You don't actually have to solve a puzzle almost ever. There's boss monsters that lock you in until you kill them, but that's it.

And that was just to provide some pacing and not make the game totally feel like a cakewalk to get to the end. That was actually a case in which I didn't throw out traditional design wisdom, which has been hard-earned over many years. It's like, if there's a hard puzzle that you just can't get because you can't read the designer's mind or whatever and it's frustrating, there's no reason why you shouldn't be able to play the rest of the game and then come back to that later. I wanted to allow that.

In fact, in Braid, sometimes there will be a puzzle that's pretty hard. It's almost like dynamic difficulty adjustment. Sometimes you'll have a puzzle that's hard in some way. "I don't get it." And then you play on, and maybe there's another puzzle that has an easier aspect of that that you can solve that will remind you of the earlier one and give you an idea. "Oh yeah, that puzzle that I was stuck on might work like this!"

So if you're a more hardcore player who wants to grind through the game, you can attack that puzzle and not give up, but if you don't do it that way, it might be a little easier, but you're still not being given hints. The game never gives you hints.

I think Microsoft wanted a hint system early on and I was like, "No. There's no way that there's going to be a hint system in this game, because it's opposed to the fundamental philosophy of the game, which is about actually understanding." So yeah, I think I talked that one dry, but I don't feel like I've quite hit the end.

When you were testing, did you balance anything as a result of that? Or were you like, "No, there's no room for balancing. Either you get it or you don't and come back to it later, but that's just how it is?"

JB: Yeah, most of the puzzles are just the best puzzles that I've found through interpretation. It so happened that there was a good difficulty variety.

That was another thing. One traditional idea of games is that a game starts out easy and then gets harder toward the end, and it ramps up, because you've got to have this challenge that ramps up. I didn't find that to be the case when I really questioned that for Braid because of a couple of reasons.

One is that it has this parallel structure. Every time you go into a new world, there's a new rule that wants to ramp up from easy to harder, at least. But then also, it's just nice to have pacing. It's nice to be playing something hard for a while and then have something easy and then hard.

If you go see an action movie, it doesn't ramp up the action until it's solid action for the last hour, necessarily. I guess some movies do that, but it's kind of exhausting. It's like, maybe you open with a big scene, then you have a rest period, then you have another big scene. Things like that.

Kind of like comic relief game mechanics.

JB: Yeah. I've had lectures about rewards -- artificial rewards and natural rewards -- and it's kind of a natural reward to work on something hard and figure it out. First of all, that feels really good, like, "Dude, I am smart. I figured this out. I didn't think I would be able to. It took me an hour of just staring."

Because Braid is not like one of those 13-puzzles or whatever where you're moving something around, or a Rubik's Cube, or anything. It's like, there's two things on the screen, and you're like, "What? It's not possible to get that thing," and then like an hour later it's like, "Oh yeah, I actually just do one action and I can get it."

That's another reason why it feels good, because it's not arbitrary. It's not like you've stumbled your way through a complex series of motions, usually. There are a couple of puzzles in the game that you can get that way, but there's always a better solution. The speed run at the end of the game that unlocks after you win it encourages you to find a better solution so that you can get through the game in the minimal time. There's layers of improvement that can happen.

But what I was trying to say is not only do you get that little rush of, "I've figured out something hard. That's so cool." But then you get some easy stuff as a little lull after that, hopefully. You can't quite predict what's easy for whom, but you don't want to bang your head against something and then bang your head against the next thing. Ebb and flow was more of the idea, so I tried to pace it that way. Who knows if I did a good job? But I do feel like it doesn't feel like traditional pacing. I think people can see that.