FortressCraft creator Adam Sawkins has rejected claims his Xbox Live Indie Game hit is a Minecraft clone and hit out at Markus "Notch" Persson and his company Mojang.

In an interview with Eurogamer, Sawkins said additions made to FortressCraft over the last 12 months make it a very different experience in gameplay terms.

Recently added features include over 20 weapons and items, voting and rating systems for servers, high-res animated custom blocks, fairy wings, lasers, factories, conveyors, jump pads, physics blocks, automated minions, copy-and-paste, night vision goggles, coloured lighting, custom world generation settings, multiple biomes, island mode and three PvP game modes.

"Minecraft is a game about digging out resources, crafting weapons and armour, travelling into the Nether, and killing a dragon," Sawkins said. "Whilst it lets you be creative, that's never been its main focus.

"You can spend ages creating amazing things in it, but Minecraft's never been about the creative aspect, any more than GTA is about making sculptures out of buses. Sure, you can do it, but the game doesn't lend itself to that, nor does it help you out.

"I'm sure the comments will disagree, but I don't see any of the Minecraft achievements saying, 'Created something awesome'. They're about crafting, fighting and travelling to the Nether, in order to complete the game.

"FortressCraft, on the other hand, has focused almost entirely on the creative aspect. It's a powerful Voxel engine; it allows complete creation and destruction of anything you want. It allows you to create high-resolution custom blocks, place them and then animate them. It has automated robotic minions to help take the grind out of creating something amazing. And if that's not enough, the game has an elegant copy-and-paste system, allowing you to create entire cities in a matter of hours, rather than days.

"Unlike Minecraft, once you've created something amazing, anyone (that you allow) can come and join the game. There's a complex server browsing system that lets you to filter the thousands of servers by multiple criteria.

"Also, c'mon. We've got laser guns, factories and trampolines. What more do you need, a gun that fires shurikens and lighting?"

"And nothing in FortressCraft is fixed. You can customise everything. So, for example, in Minecraft, you can make ladders. They look identical in everybody's world (barring hacking the game, of course). In FortressCraft, a ladder might look like a futuristic elevator, a fireman's pole, a cartoony 'up' arrow or just a boring old wooden ladder. This customisation applies to almost everything, with plans to allow the currently non-customisable stuff to be customisable in the near future.

"Also, c'mon. We've got laser guns, factories and trampolines. What more do you need, a gun that fires shurikens and lighting?"

Despite the changes Sawkins has made to FortressCraft since launch, he has been dogged by criticism from gamers who dismiss his creation as a clone.

Sawkins said he understood these claims, but insisted the word "clone" was being misunderstood by many of his critics.

"Whilst *I* understand why it might be called a clone, I'm also an (ex) industry professional," Sawkins said. "A clone, in gaming terms, is a game in the same genre, that shares one or more major features.

"I had the immense honour of working on the Burnout series, and anyone who worked on that would gladly call it 'An Outrun clone' - because it was. The eighties was awash with Gauntlet clones, the nineties with Wolfenstein clones. It's not an insult, it's a handy way of describing the basic premise of a game.

"Both FortressCraft and Minecraft are about walking around a vaguely-Earth-like perlin-landscape, rendered using Voxels, and both allow complete alteration of that landscape. Passed that, the similarities run out really quickly.

"Both Twisted Metal and Gran Turismo are about driving cars, on Earth. The cars tend to have four wheels, run on tarmac, and there's even car damage in both of them! Now, no-one in their right mind would call them a clone, but it would be very, very easy to take a bullet point list of features, and make the games out to be almost identical.

"However, it seems that the common-or-garden gamer these days takes the term 'clone' to mean 'carbon-copy'."

Sawkins sent Eurogamer these two pictures, which he said address the problem.

"I defy anyone to call FortressCraft a 'carbon-copy' of Minecraft after having seen those," he said. "It simply doesn't apply."

FortressCraft, a £2 title, is the most successful game on the Xbox 360 XBLIG platform. Total sales have generated "well over" $2 million, "with no signs of slowing". "I receive most of this money, but I make sure that the people who helped me get my game to where it is are suitably rewarded" Sawkins said.

And comparisons with Mojang's game are set to intensify when Minecraft is released on Xbox Live Arcade later this year.

We asked Sawkins if these comparisons were fuelled by his decision to name his game FortressCraft.

"How many people run around shouting that Zachtronics should sue Mojang? Minecraft stole half the name, the basic idea AND the graphic style from Infiniminer," Sawkins replied.

"Why am I apparently held to a different set of standards? I actually had an eight hour chat with a bunch of friends, trying to come up with a name that indicated the voxel heritage, wasn't already taken, and was a good name.

"It's actually very hard to come up with a good name for a game these days; you might as well just say that it's a game, with zombies in it..."

Sawkins pointed to a chart, below, that he said proves "there's nothing that FortressCraft shares with Minecraft that it does not also share with Infiniminer, which pre-dates Minecraft".

"So people could just as easily claim that I ripped off Infiniminer instead, but they don't because Minecraft has had more exposure (and they may have never heard of Infiniminer)."

He added: "It honestly comes across as nonsensical as claiming that PGR rips off Gran Turismo; they can both trace back to a common heritage, they're in the same genre, and thus they obviously have many, many similarities. But it's the differences in games that make them interesting, not the similarities."

Last year Sawkins called out what he described as the "Notch Defense Force" - and in doing so angered many Minecraft fans.

"It appears the NDF haven't gone away," he told Eurogamer. "I still get people commenting on 12 month old videos, telling me that it's exactly like Minecraft, and Notch will sue me 'when FortressCraft is released'. It's a pity that you can't test for ignorance before commenting on YouTube!

"I'm still offended at Notch's comment: 'FortressCraft is an obvious attempt to just take something popular and clone it as closely as possible.' He hasn't played the game, just watched a video on it (according to him).

"If I was attempting to copy Minecraft, I wouldn't have wasted my time on the creative aspect, on the shiny new graphics, on forming my own little niche in the games market. I would have just copied the crafting, the shitty melee combat, added in a teleporter to another dimension, stuck in creepers and sheep and, er, cats. But I didn't. I took it in its own direction.

"I'm also still pissed off that Notch had a go at me on Twitter for not crediting him, directly insulted me, and still managed to gloss over the fact that I do credit Minecraft and my other inspirations in the credits. He then went on to start slamming Total Miner and when I stepped in to defend it, he blocked me on Twitter; I guess that's one way of dealing with criticism."

"Everything in Minecraft was taken from previous games; mixed together and put into one wonderful package, yes, but actual innovation? Zero."

Earlier this week Minecraft maker Mojang accused Minecraft clones of failing to do anything new - but confirmed it had no intention of suing their makers.

Mojang business chief Daniel Kaplan discussed the issue of Minecraft clones in response to a Eurogamer-asked question in a webchat.

We asked Kaplan for Mojang's take on FortressCraft, and asked if it would take Sawkins to court.

"As long as they don't use anything we MADE, we don't care," Kaplan replied.

"Like, would the Doom creators sue everybody who has done an FPS? Don't think so."

He added: "I'm really bored by the clones. They don't bring anything new to the table which is really sad."

Sawkins also had some choice words for Kaplan in response to his comments.

"He's referring to Total Miner (incredible depths, collecting blueprints and fighting monsters whilst using loads of customisable avatars), Castle Miner Z (where you fight zombies with f***ing assault weapons for heaven's sake) and FortressCraft (which is, I believe, the world's best creative-voxel game and allows you to create things that are impossible in any other game). Do they sound like carbon-copies of Minecraft?

"Mojang needs to realise that they are now the 800lb gorilla of the VoxGame genre; to arrive onto the Xbox and to bad mouth and lie about their competitors puts them firmly into the realms of EA or Activision. Whilst I might complain heavily about Minecraft's horrible combat or broken minecarts, I would never acknowledge it as being anything less than the Indie game that made Indie games cool again.

"Because I would truly love to hear back from Daniel Kaplan about what Minecraft 'brought to the table' because, as far as I'm aware, Minecraft didn't invent or create a single new feature. Not one. Everything in Minecraft was taken from previous games; mixed together and put into one wonderful package, yes, but actual innovation? Zero.

"And as for my comment about 'Why would anyone buy Minecraft?' - I was happily vindicated there. The Minecraft fanboys rushed to its defence. Bear in mind, this was six months ago. At that point, there was precisely zero information available about Minecraft 360. And yet I was told that I would be 'crushed'. So, what can I ascertain from that? That people will base their decision to buy a game on its name alone.

"This is a horrible, horrible state of affairs for the games industry. But, of course, people still quote me now - as did the Eurogamer article. Still, I don't actually know why anyone is excited for Minecraft 360 - you can already buy Minecraft, it's been out for four months. It'll be better on a keyboard and mouse, too!

"Maybe the Kinect support will be amazing!"