Spelunky 2 is so ambitious that even Derek Yu doesn't know what you'll find in its darkest depths

On December 21, 2008, Derek Yu released an experimental piece of freeware onto the internet. "Hope you enjoy it", he wrote in the accompanying post, "I am eagerly awaiting your feedback, whether it's good, bad, or frickin' beautiful." The first players got spelunkin', and the rest, as they say, is history. 

12 years later, Spelunky is considered one of the most important games of its era; a catalyst for the indie scene that popularised the roguelite genre and inspired countless developers to try their hand at solo game creation. Now, Yu is returning to his subterranean sandbox with an official sequel, Spelunky 2, and we speak ahead of its September 15 launch, discussing everything from its State of Play trailer to streamer culture.

"The first Spelunky never felt like the end of the series to me," he tells me of the sequel's origins. "It always felt like there was a lot more that we could do with the core concept and mechanics. After the PC release of the game, I wrote a book about it for Boss Fight Books and spent a lot of time thinking about its development, which gave me a better sense for what a sequel might look like."

"What really made the project real for me, though, was being able to work with BlitWorks and [Spelunky composer] Eirik Suhrke again. I knew we'd be able to expand the sequel the way I imagined with this team," he adds. 

Blitworks, a Spanish studio primarily known for porting indie titles to new platforms, has been working with Yu on the programming side of Spelunky 2's development to help bring his vision to life. The sequel, with its expanded scale and suite of new features, was far too ambitious to be tackled as another one-man job, and Yu says the studio's involvement was "an absolute requirement" for meeting fan expectations. 

"I had to know they were on board before spending too much more time thinking about it," he says. "In order to make a bigger game and let people play online... and do it all in a reasonable timeframe... it definitely required a larger, more experienced team. This is also the first Spelunky game where I've asked another artist to help me with illustrations. Justin Chan's done an amazing job bringing the characters, world, and story of Spelunky to life."

Sound of the underground

Like its predecessor, Spelunky 2 is a game that delights in the unpredictability of its underworld. Yu jokes that there are secrets in the game that even he doesn't know about, as its emergent, procedurally generated assets are like a periodic table of chemical elements, primed and ready to interact with one another in all manner of unexpected ways, with the player being the most independent variable of them all. 

"We're always sharing crazy things that happen in-game amongst the team, and I can only imagine what's going to happen when Spelunky 2 is released to the wider world," teases Yu. "With a roguelike-inspired game, it's important not to be too strict in your approach to balance, because you can inadvertently remove a lot of fun moments." 

"When I look at a potential exploit, I have to think about its impact across many runs," he continues. "Is this something obvious that players will want to use every run, limiting their creativity? Or is it something that you can only use one out of every hundred runs, or only if you know the game really well?"

In addition to the game's expansion of tools, zones, enemies, mechanics, and features, the story of Spelunky has been significantly broadened, from what was once a simple concept (digger goes spelunking) to a sci-fi adventure anchored in heart-stirring themes of family and kinship. The addition of local and online co-op means there are now more playable characters than ever, too, from OG Spelunker's daughter, Ana, to an anthropomorphic sloth.

Another new addition is your Base Camp, where you'll be able to chat with other characters you've met, and generally take a respite from the dangers of the caverns beneath. Yu explains that this focus on building relationships both with the co-op friends you play with and the characters you find in Spelunky 2 "are inspired by my family, as well as the real life Spelunky community, and how important it's been to the continued life of the series."

"In Spelunky 2, I really wanted to build up the lore and give each character more personality and backstory," says Yu. "None of this additional narrative will interrupt the basic flow of the game because a lot of it is relegated to the journal and Base Camp, which is essentially an expanded version of the entrance room in Spelunky 1 where you could start a run or use shortcuts."

"Ultimately, the stories the player creates are the most important to Spelunky, but it makes their stories richer if the game's world feels like it's a living, breathing place."

Cave calamity

When Spelunky first launched, streaming was in its infancy, but its successor is releasing to a world that is just as interested in watching people play games as playing them for themselves. Add that to the fact that there's now an established community of Spelunkers, ready to pore over every procedurally generated pixel from day one, and Yu wonders whether Spelunky 2 will be able to recapture the mystery and magic that surrounded the first game's launch.

"I never hold out much hope for my intentionally-hidden secrets to last long, especially since Spelunky has a community of dedicated players now," he says. "I'd be happy for those secrets to last a few months. I can't say for sure! That's the exciting thing about releasing a game, especially a roguelike-inspired one – it's hard to know what's going to happen to it once it's out of your hands."

As for Spelunky 2's future, Mossmouth has already confirmed the game will be hitting PC a few weeks after its PC release, and Yu says you can likely expect further platform ports to arrive sometime in the future following that. Don't hold up hopes for any major DLC expansions to the game's core Adventure Mode, however, as the creator says the release build "feels pretty complete to me".

"The game will certainly be supported better than Spelunky 1 after release in terms of bug-fixes and improving the overall experience. That's another area where working with a studio like BlitWorks is critical. And this is the first game they've developed from scratch – they're primarily a porting company, and a great one, at that. So we'll be looking at other platforms after Spelunky 2 releases on PS4 and PC."

It's a testament to the perennial delights of Spelunky that players are still religiously enjoying the game to this day. Spelunky 2 threatens to finally offer that community something else to move onto, but it's taken over a decade to get here. Like that of the original game's mascot, many of Spelunky's fans will have grown up, got married, and even had children in the time between, yet the call of underground still beckons them beneath the surface for just one more run. 

The sequel won't be changing that ritual, but merely enriching it, while also introducing the joys of spelunking to an entirely new generation of players. No wonder Yu doesn't mind that his biggest secrets will likely get found out within the first few weeks. 

For more, check out the biggest upcoming games of 2020 and beyond still on the way, or watch below for our latest episode of Dialogue Options.