GamesBeat: I always found it interesting that Peggle, which is a fantastic game, never got the clones that other match-3 games had. Do you have any insight into why that might have happened?
Andrea Roberts: My gut reaction is I don’t know. It felt so great. I really don’t know why more people didn’t play with it. The physics is definitely a challenging side to it. Kurt is a great programmer, so that made it easier for us. But getting the — it’s a real-time physics simulator, and getting that all to run well on a range of devices was a big task for us. I can imagine it’s not something easy to throw together real fast for —
Bob Roberts: It might be that phones and those kinds of things are now getting powerful enough that it’s not as bad as it would have been back then, when it first came out. It’s a much lighter-weight, simpler, easier thing to throw together with a cheap processor than in those days of phone power. You can handle it more easily.
GamesBeat: How did you pull off the physics? Are you using any sort of plugin or physics engine for that?
Andrea Roberts: We developed the game in Unity, but we used Bullet Physics as our base for the physics.
Bob Roberts: They have a pretty tried-and-true, tested engine there that Kurt pulled in and integrated into Unity. That’s been our base. We didn’t write a physics engine from scratch. We used something that had been put through the wringer and optimized quite a bit already and combined it with what Unity has for us to work with.
GamesBeat: Was that a challenge, or do they work pretty well?
Bob Roberts: Since Kurt’s not here, it was just so easy. [Laughs]
Andrea Roberts: We’ve had some bugs along the way that we had to wade against. The code had some stuff that needed to get fixed.
Bob Roberts: It’s hard to say how difficult something is when the person responsible for it is just super-talented and can make hard things seem easy. He didn’t ever tell us that it was undoable at any point. He just made it work.
GamesBeat: One of my favorite parts is when your hero bounces off the cushion and into the screen and they have this big smile on their face. How did you come up with that?
Andrea Roberts: Originally, when the hero bounced off the cushion, they just kind of bounced up and out. It looked very similar to when they hit the spikes. That was a really great point of feedback that we got early on. I showed it to some game developers up here in Seattle, and I remember somebody saying, “I can’t really tell the difference between hitting the cushion and hitting the spikes.” There’d been a lot of passes on feedback throughout the game. We added more audio and more screen damage effects and things like that to try and sell that. But I knew that I wanted something more visually obvious in the distinction between the two.
I don’t remember exactly how it came out, but the idea of the hero jumping out of the screen — there’s kind of this theater metaphor going on in the game. Even though the game is completely 2D, I hope everyone sort of has in their mind this little puppet theater box that you’re playing in. The main plane is all the monsters and the spikes along the bottom, and obviously you don’t want the hero to hit the spikes, so they pop out over the spikes and then run their little way down behind the curtain and back up to the top.
Bob Roberts: There’s a little door on the side of the UI, on the bottom left. Can we see them run in the door and head up the stairs? But also just generally, Andrea’s always been good about pushing for weird little charming details … when you’re trying to prioritize all these big complicated tasks, they seem like small things that maybe people won’t notice, but when you get enough of those little details in and people do take notice, it feels more alive. Giving the characters each their personality — the warrior with his goofy cackling that he does every time he gets shot out of a ballista or bounces off the cushion, or the wizard with her endearing — [Andrea’s] always just pushing for trying to get the character’s personality to come through in every animation you get, every bit of feedback that we can put on them. I think a lot of it comes from that.
GamesBeat: Did you both collaborate on the writing? Because it also has a lot of fun and silliness in it.
Andrea Roberts: Thank you. Yeah, we both did a lot of the writing. I came from a narrative design background at one point in my career at Microsoft. One of my favorite projects I worked on there was Fable III. I love funny games, and I’ve learned from some really great humor writers.
Bob Roberts: One of the guys that was a writer on Fable with Andrea — I eventually stole him to work with me on Middle Earth: Shadow of War over at Monolith — Rich Bryant. He helped out as well. He gave us some feedback and is just a generally hilarious guy who we can bounce stuff off of. I think Andrea got a lot of basics working with him on Fable.
Andrea Roberts: Yeah, he was a great sounding board.
GamesBeat: How did you come down a class structure of warrior, rogue, and wizard, and why did that feel right?
Andrea Roberts: We always refer to it as the classic trifecta. Warrior, rogue, wizard, you have these patterns in all different kinds of RPGs. We’re matching up to the same sorts of patterns — it’s a little bit different in our game — but the warrior is the tankier character. You have a lot of health. He has a lot of ways to regain health. We often think of him as the starter character. He’s a good one for you to get in and get a feel for the game. He has lots of skills, but you don’t have to be quite so active with them, so if you’re coming from more of a Peggle background, it’s a good intro to where the game can go.
The rogue, they’re all about control. The rogue has double-jump and ranged attacks. The rogue can really get around the board. He can be very precise and controlled. The rogue was often our real leaderboard player. The rogue typically — it changes up every week and people can put together really great builds for any of the heroes, but the rogue is one of the most consistent leaders at the top of the leaderboard because of those skills that they have.
And then the wizard, she’s the glass cannon who can do massive bursty kinds of attacks, and it’s all about using skills as much as possible. She has the most mana. She has the most ways to regenerate mana. And also she has the least health, so you really need to be using those skills if you want to survive at all, but she also plays with chaos in her skills. Some of them are a bit harder to control, or have some chance effects on how things work out. We think of her as more of the — she can be one of the harder characters to survive with, so she gives a bit more difficulty. She can also be one of the most surprising characters, if you’re looking for a more chaotic, silly run.
GamesBeat: The mage’s lightning bolt and how it sweeps the board: How did you come on to that, instead of just a lightning bolt that would fire off and bounce?
Bob Roberts: I think we were brainstorming — since the wizard was the last character we built, we’d made the warrior and the rogue and shown them off for a while at various meetups and shows and stuff like that. We made the wizard late. As we were brainstorming around her mechanics, I think we were just trying to mine different character ideas. “What haven’t we done yet that plays with the screen space and with predicting trajectories?” Having that need to think about the angles as you’re bouncing around was just a different feeling. It was another principle that Andrea was pretty strong on as we designed the characters, not wanting there to be too much overlap in their skills or their bonus properties or things like that. We toyed around with versions where you could aim it, things like that, but then we didn’t want it to feel too much like the rogue, who has all the more controlled aiming stuff going on. Playing around with — it was actually pretty late that we put the pre-vis lines in. Those used to be a bonus property, where you could see where the angle is, but we found that there was so much going on that seeing those lines wasn’t taking away the skill of timing those angles. It was just helping more people connect with that aspect of it. Just bouncing around and seeing the angles of the board from different perspectives as you’re in motion.
GamesBeat: At what point did you decide to add in the Slay the Spire-like gating of levels, instead of going linear from one level to another?
Andrea Roberts: That was pretty early on. Our first one-pager was more of a linear … [but] we always wanted to have different paths, but we thought of it more like there would be a bunch of set challenges for each hero. You’d move between them. But we really loved roguelikes. I’d really been getting into roguelikes around that time in particular. One of the weird things — I’ve always found procedural generation super-interesting. But it had also become attractive to me at the time after having a kid and finding that I really didn’t have that much time for playing games, as much as I’d used to. Roguelikes became something — it was really nice to have this feeling of one run, where a typical run will only last a half an hour to an hour and a half. I’ll die, whatever, but it’s something like — I can get in and play and know that it was going to be over fairly quickly. I could know I could come back tomorrow and I didn’t have to remember where I was in the game. Something about that was attractive to me at that moment. And so we’d been talking about it a lot. Could we make the game into a roguelike? Could we procedurally generate the levels? There was some concern about if that would be way too much work, if we would end up losing some of the charm and control of handmade levels. And then we went to — I think we’d only been working on the game for about two months, so we’d just had our first vertical slice prototype at that point.
But we went to the Seattle indie meetup — there’s a group that’s really awesome, that supports all the local devs, and they put on a ton of events. One of the events they do regularly is this show and tell where any developer can come in and drop off a laptop and let people play at any stage of development. I think it was probably the first time we showed the game off to anybody. We brought it in and at that same event, the Slay the Spire guys, who are local to us, had brought in Slay the Spire. I think they were about six months at that point from releasing it in Early Access, so we hadn’t seen the game or heard of it before. At that show, each one of us had gone over and played Slay the Spire and come back to talk to each other. “Oh my god, that’s such a good game. It’s going to be so much fun.”
Bob Roberts: And specifically the vast structure. We had, just a little prior to that, played a bunch of FTL, which has a very similar map layout that you progress through as your campaign. It was reinforcing that that kind of campaign map structure is really compelling, and a randomized version of that is compelling to all of us. OK, yeah, that cemented it. Let’s talk about what it would really take to embrace that sort of loop.