Pre-order Borderlands 2 and you'll receive the Mechromancer character free of charge when the DLC is ready, but there are many more characters which could be introduced, says Gearbox boss Randy Pitchford.

"I had this idea, why should there only be four characters, and can we add more after we launch the game? We talked about it, and thought there were some technical challenges to that, but our lead programmer, Steve Jones, working with his engineering team, figured out how to adapt the software so that if we wanted to create new characters, it could accept them. The software can accept them as plug-ins, almost," Pitchford told "They did the work to create those hooks so that we can make a plug-in of a character, basically. I'm simplifying it by calling it a plug-in, but I think it helps to articulate it without getting too technical."

He added: "We talked to 2K about it and they were really cool. They said, 'If you guys want to do that, that's awesome.' But I said, 'Here's the thing though: I want to test it first, but we haven't built it yet. I don't want to build it until we test it, which means I have to take the risk to talk about it, but if you talk about it before the game comes out, there's the whole DLC Day 0 problem. We haven't even crafted the thing yet.'

"So 2K said, 'Well why don't you do this: it'll be done when it's done, but if people pre-order the game, let them have it for free.' And so that was kind of a cool way [to do it]. I was able to go to PAX and say, 'Ok, we have this idea - but it's a proposal. What if we added a character after it ships? Here's what we're thinking, we have a sketch, here's the idea. We haven't done any work on it yet, but if we do it it'll be done about 60 to 90 days after the game launches. It'll be DLC, but because we want your opinion on it and we know you'll freak out if you think we're going to milk you, why don't we offer it to you for free if you pre-order?'

"Because most people buying the game aren't pre-order people. There's going to be a lot of people pre-ordering, there already is. A crazy amount of people pre-ordering."

Pitchford says that once Borderlands 2 goes into certification creation of the Mechromancer will be one of the first things the studio does.

"Fortunately that doesn't take the whole team. It requires Jonathan Hemingway's neck-deep or animation team. I mean, it's a lot of work to add a character, because the character has to be balanced for the whole game. We're not just going to have one section of content, you can play the whole game with them. So it is a lot of work - it's character designers, artists, game designers, it's animation, programmers. There's going to be a team that, as the game goes into cert, they'll be the ones who will rampage through that, and see what we do. If it goes really well, maybe it comes a little sooner; if we run into problems, like if some of the designs need some iteration or whatever, it might take a little longer. I think the 60 to 90 days window is pretty safe."

And what of even more additional characters appearing as DLC?

"I'd love to. That's kind of why we put the hooks in, I'd love to - but we'll have to see how it goes. We literally have no plans beyond the Mechromancer, but we'd love to make some," said Pitchford.

"But the other thing too is that even just thinking about the Mechromancer as we did has been risky, as what we really should do is dedicate all of our attention towards shipping the game. But you know, since Scott was already done he was able to do some concepts there, and it was smart for us to put the hooks in. Just in the same way we put hooks in to allow DLC to be added on, we now have the ability to add characters."

And additional characters doesn't necessarily mean all-new characters.

"I can imagine a lot of things. I can imagine the creation of characters who are wholly original, and I think there's going to be some demand for the original player characters - again, knowing that we're all talking theoretical and hypothetical here. I think there are some NPCs we loved. Wouldn't it be interesting to play as them? I want to be Moxxi! What would Mad Moxxi be like as a player character? But we can't do it all at once, it's a stupid amount of work. Building a character in Borderlands is an absurd amount of effort, it's an insane investment."

Pitchford concluded: "Mechromancer is an exploration, we'll figure it out and see what happens."

Borderlands 2 will be released September 21 for Xbox 360, PS3 and PC.