Since it launched last year, Heroes of the Storm has become one of the most popular MOBAs in the world.

Its success can be put down, in part, to how the game pulls its playable characters from all four of Blizzard’s main franchises. But gameplay is also very different from rivals like League of Legends or Dota 2, with a focus on shared experience points and the complete absence of attainable items.

At last week’s Blizzcon 2016, Blizzard showed off two new heroes – Ragnaros and Varian Wrynn – set to be added to the game later this year, as well as hosting an esports championship that saw masses of fans turning out to watch the action.

With Blizzard’s MOBA tour-de-force now seemingly unstoppable, we spoke to two key Heroes of the Storm developers about the game – past, present and future. Here’s an exclusive Q&A with Senior Game Designer Meng Song and Senior Artist Phill Gonzales.

During my time playing Ragnaros, I found him to be extremely overpowered, without any real downsides. Would you agree?

Phill: It’s kind of common. We feel that the new characters, they come in and they’re a little overwhelming at times because we haven’t played with them before.

In our internal play-tests, we’re working on heroes that our going to come out in the spring, and so there are maybe five heroes that the roster is completely unused to, and so we’re like ‘what is going on?!’. And so having both Ragnaros and Varian show up is like a little taste of that madness that we experience internally.

And the new characters, it takes a little getting used to sometimes. But the balance designers are always very intent on testing as much as possible, trying to drop a hero into the Nexus at a 50% win-rate. And if that needs some more adjusting, we play close attention. There’s simply only so much we can learn from our limited pool of testing. Once it goes out into the community, it is off to the races.

Is there too much warning for the Ragnaros lava wave ultimate?

Meng: During our internal play-test, we got a lot of complaints from testers, because the lava wave deals so much damage. If you can’t get out of the way in time, you die. And if a Ragnaros player casts a lava wave with good timing, and they cast the wave before the team fight happens, a lot of people get caught and killed.

We started to feel that it was imbalanced and not fun for the player who got killed by it. So one thing we did is to create a very obvious warning so that everybody knows in advance. Because the fights are so intense, sometimes people get caught up by one thing, and they still ignore the warning. But those moments are fun moments.

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How long does an average hero take to design?

Meng: For one hero, I think on our side, it’s about two months. And then adding the art side…

Phill: Probably, when we’re all said and done, we’re looking at a seven-to-nine-month spin-up time. And this is from the really early stage where we’re just talking about it, to having meetings talking about what it’s going to look like, sound like. And then that process gets drawn out, as it goes from play-tests to being ready to be able to actually make a 3D model.

And then it’s all wrapping-up. We test it super thoroughly because we make a hero and we make a master skin in tandem with that as a progression reward, and we always have a launch skin. And all those are happening simultaneously, being tested, and getting all the promotional stuff spun-up – the videos and the behind-the-scenes looks and stuff like that.

So it’s kinda crazy how long it takes. When we did our deep-dive panel, the date on starting Varian’s model was in February, which is just insane.

Meng: Ragnaros was even longer.

Phill: Because he’s just way more complex. He’s almost as much of a special effect as he is a character. So we were doing lots of lava work for a long time.

What was the biggest design challenge for Ragnaros?

Phill: The immersion problem. The feeling of him being a raid boss.

Meng: So for Ragnaros, the design wasn’t a straight line like for a lot of other heroes. Because Ragnaros is a boss, right? In WoW, when you do the raid, you see this boss occupy the full screen. It’s even bigger than our Core, which is the biggest building in the game.

He has a trait that you can use to take up a building, and at the early stage, you were always the building – you basically replaced the Core. But during our internal play-testing, people were saying: ‘Although I know Ragnaros is over there as the Core, I never got in to activate it, because I never see it. All I see is the front gate over there as the Core.’ Only when the player actually pushes to our base do they see the Core. But that’s not a fun moment because you are losing.

Phill: When we do heroes, when they’re behind the lines, that immersion gets lost really quickly. You just don’t have that sense of presence Meng’s talking about where you see him, you interact with him, it’s actually happening.

That was an early problem we had with Abathur too, until we developed the Symbiote and all that stuff. We iterated quite a bit with Majordomo being out on the map representing Ragnaros. The Son of Flame was there for a while. But it just felt better if it was Ragnaros himself, and then his trait allowed him to become the Molten Core boss we want to fight.

Meng: And the hero designer – I remember, it’s Jake – later on tried to solve the problem with the presence of Ragnaros. He came up with an idea to give Ragnaros the ability to teleport onto the battleground. But the problem was that Ragnaros was the Core, so when you teleported, physically you teleported the Core onto the frontline. And then the enemy team was like: ‘Oh, this is a great opportunity. Let’s kill the Core.’ So it created a lot of chaos. We didn’t really have a way to balance it.

And what was the hardest thing about designing Varian?

Phill: Visually, he was pretty straightforward thankfully.

But in terms of game design, because his talents allow him to have three different specifications, the most challenging part was actually the animation budget. In terms of animations, it’s really expensive to have Varian switching all that equipment and animating differently when he equips different swords.

But it really pays off. When you make that talent choice, whether it’s the Colossus Smash or the Shield Break or the Twin Blades, he holds those weapons differently for each one of those choices, and that’s very special. It’s really cool.

How do you decide which character to turn into a hero next? Do you choose popular characters, or ones you feel will bring a skill-set you think is missing from the game?

Phill: It’s a little bit of everything, right?

Meng: I remember for Varian, we sent out a questionnaire to the team saying: ‘Hey, which hero do you want to see next?’ We also get a lot of feedback from the community. We released Tracer and we released Zarya; we released a lot of Overwatch heroes because people were asking: ‘Hey, can we get a hero from Overwatch?’ Other than that, I think once we get a small collection, then we’ll say: ‘This year, we released Overwatch heroes. Next year, maybe we’ll release World of Warcraft [heroes].’

Phill: There’s a feeling from the vision holder, the high-end of design, saying we need more assassins, we need more tanks, this is the quota we want to fill to bring up the roster. And on top of that, we wanted to present Starcraft to this capacity, Warcraft to this, Overwatch, Diablo, whatever.

Meng: Sometimes the other factor we consider is that we want this game to be different in this genre. We want the design to be out of the box.

For example, for Varian, we wanted to shake up the design of the draft process. We feel the draft process is a little bit streamlined, and doesn’t have a lot of exciting moments. So Varian is designed to say we put in something that you don’t know what class it is. Now how will you pick against it? That kind of thought also comes into the decision of which hero to make.

Are you going to release Overwatch heroes faster to bring that IP up to balance with the other games?

Phill: I think based on what’s going on internally, we are catching Overwatch up a little bit. And I think that’s good. Warcraft is a pretty expansive universe and we’ve drawn a lot of inspiration from it. And Starcraft, we’ve hit a lot of the major notes too.

And Diablo and Overwatch are those ones that are just really rich, they’re always wealthy for things we could incorporate into our games.

Especially with Overwatch, we’d love to catch up and have that same presence for the Overwatch players as we have for the other universes. As we’d ideally want to have, at the very least, an Overwatch tank, specialist, assassin, so all those roles are filled. So if you had daily quests like play three games with an Overwatch hero, and a specialist quest, we could have those bases covered. I know Matt [Cooper, Senior Game Designer] was pretty insistent on that with the Starcraft characters a year or two ago.

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Are there any characters you wanted to bring into Heroes of the Storm that just didn’t work out?

Phill: When we developed Artanis, we would have been releasing him before Starcraft: Legacy of the Void came out, which is something we do have a really big concern about. Artanis was majorly developed in the Void, and it would have been us getting the jump on them by releasing Artanis early.

We were talking about Fenix, at the time, who’s another really popular Zealot character from StarCraft 1: Brood War. And the big lore hit about Fenix is that Fenix is a really prominent Dragoon, and the lore behind the dragoons is that when a templar falls in battle, if he can be resuscitated, they can put him in this dragoon met and he can fight again. And we said if we do Fenix, people are going to be very adamant that we support that dragoon fantasy. When we were talking about this, Leoric wasn’t that old at the time. So that game designers had a real concern that this is another character with a resurrection mechanic.

One of the other prominent versions of that is that we were developing Heroes before Diablo 3 had released. And that’s why our version of Diablo is the Diablo 2 one, because we didn’t want to spoil the storyline and have the primeval Diablo appearance be released before Diablo 3 ever came out.

One of the big criticisms about the game is that once a team starts snowballing, it can be a little overwhelming compared to other MOBAs. Is that fair?

Meng: I think our game actually has the most comeback mechanics. And I see a lot more comebacks in our game than other games in this genre. I play a lot of other games in this genre as a designer, so I can do the comparison. In other games, a lot of times if you are behind on gold or experience, especially the gold, sometimes you feel like you don’t have a chance. You just want to type surrender.

But in this game, even if you are two or three levels behind, you always have a chance. For example, the experience mechanic; if you’re behind, you get a lot more experience by doing the same thing compared to the other team. So even if you are ahead of the other team, you have to always be concentrating on the game.

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Have you found keeping the game balanced more or less challenging than you expected?

Meng: It’s definitely more challenging. Unlike other games, we have more battlegrounds. We have very outside-of-the-box heroes, like Abathur or Murky. In some other games, if one hero keeps dying like Murky does, and the other team loses, they’ll say: ‘That’s a feeder’. And I still remember at the beginning of this game, people were saying that Abathur is an AFKer, because she always stays inside the base.

We put a lot of pressure on our balance guys, but our balance guys are really talented. So far, our hero balance in super good. We all love the work they have done.

Vainglory has been hugely successful as a MOBA on mobile devices. Have you considered putting Heroes of the Storm on mobile too?

Phill: I haven’t seen that consideration, but there was a very early iteration of the game where someone was playing on an Xbox. I was like: ‘Oh my goodness’. It was actually our executive producer. So I don’t know if there’s any plans for this bigger features. I’ve seen it happen and thought it was pretty amazing. But in terms of mobile, I don’t know what the plan is.

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What do you think of Heroes of the Storm? Let us know in the comments.

Deputy News & Features Editor Writer.