Ru Weerasuriya is co-founder and creative director at Ready at Dawn, whose most recent release was God of War: Ghost of Sparta on PSP.
"Uncharted 2: Among Thieves. It finally bridged the gap between traditional gaming and what we need to expect in the future from everybody in this industry.
"Every developer needs to take a hard look at what we need to do for the future. Naughty Dog were the first guys to really provide a full entertainment experience, like the kind of things you normally only expect out of movies. This was a complete interactive entertainment. That's a huge jump from where we were."
Maxx Kaufman is game director at inXile on Hunted: The Demon's Forge, published by Bethesda Softworks.
"I'm going to say System Shock.
"I played a lot of games before that, but I really love that cross between RPG elements, shooters and just losing yourself in that world; immersing yourself in that world.
"That's really what we're trying to do with Hunted - we're trying to immerse you in this world and give you depth and variety, but give you faster-paced action, and get you a little closer to make it gritty as well."
Yuji Naka is boss of Japanese developer Prope and one of the creators of Sonic the Hedgehog.
"It is hard to think of anything particular which influenced me the most. As a developer, I get influenced by many things on daily basis; games of course, films, people I meet when I travel, etc. It is important for us creators to be stimulated, and learn from many things in everyday life."
Adrian Chmielarz founded People Can Fly, now owned by Epic Games and developing Bulletstorm.
"Modern Warfare offered me an experience I did not have before. Was I immersed in games before? Of course. But this sort of experience, when you let go of the controller and you go, 'F***.' When that atom bomb went off... That doesn't happen. That's not how it is. They were supposed to survive. It's a simple thing that was done in movies many times, but this first-person immersion – such a deep immersion that you actually stop playing and just enjoy soaking in the moment, and you're overwhelmed by emotion at this point – that is something that happened to me for the very first time.
"I always tell our guys that after that nuclear bomb went off, nothing was the same in the game business. You have to step up your game. You have to offer the same kind of experiences.
"It works out very well for me, because what I am interested in is taking players to other worlds. I'm never going to be a space pirate. I'm not going to be a Navy Seal. But if you give me a game that sells it, that I can really feel like I'm there, it's probably 20 per cent of the real feeling, but it's still some percentage of the real feeling. So we try to offer the same thing, in a much lighter way, of course.
"If there is a bible of 10 games you have to play and understand and dissect if you want to be a good designer, Modern Warfare is on that list."
Sean Murray is co-founder and managing director of Joe Danger developer Hello Games.
"I'd like to choose something really different that no one else is going to say, but I can't - the honest truth would be Mario 64. It's too obvious. Minecraft! Only now!
"But that's got to be for most people - Mario 64 is one of the greatest games ever made. The thing I always say about it is that it was the first proper 3D platformer I played and had seen, and the team that made it had never done a 3D game before. Imagine that they got everything right! That's amazing to me. And the rules they set down are set in stone now. For about 10 years afterwards everyone tried to do poorer versions of that.
"It was that exact thought that made me get into games - somebody's just sat down and thought, 'I will make a 3D platformer,' and nailed it, and thinking about all the design decisions in their heads and all the iterations, and thinking that would be so much fun to do.
"And for a lot of people, you can't say this with books or films, but if you make a game it might be the first game somebody has ever played. Mario 64, for loads of people, is probably the first game they've ever played.
"Imagine that. You could only do that with a book if it was a kids' book, but with games you can just make a game and it can be their first game."
Peter Molyneux is creative director of Microsoft Game Studios in Europe and co-founder of Fable developer Lionhead.
"I think it's probably ICO.
"You go back to that title and have a look at it - there were no icons on screen to speak of, the story was told in such an amazing way, it was told without language, it was incredibly iconic, the environment still is one of the most mystical, enchanting environments ever made, its gameplay with the hand-holding mechanic was brilliant.
"It broke every rule of gaming when you think it didn't have tangible foes, it only introduced the baddie very late on, mystery was part of its mechanic, it didn't have real power-ups or anything. It was genius and it still remains a work of genius.
"If I made something like ICO, I'd be very happy to die."
Compiled and edited by Tom Bramwell and Wesley Yin-Poole. Enormous thanks to everyone who contributed.