He says on his website: "When you're writing something like Hope For The Future, which is custom made, it is like doing a portrait for someone. You have to use your imagination and work out what they need, what they're going to want and then what you want to give them.

"Then you've got to combine those three things into something that you still think maintains integrity. So in the game you're basically trying to save Earth from the invaders, the aliens, so that suggested to me the hope for the future idea and I went from there."

He continues: "Then I thought it is not just a game song, this will get played outside the game so it has to stand alone too, you can't have references to aliens or people will think, 'What's he talking about?' So it had to have its own stand alone meaning and integrity."