Usually when you go to use, buy or borrow an engine, someone will say, “Lend us your name,” or of course ask for payment. We had no contract with Guerrilla Games, but when we met them they suddenly gave us a box, a very pretty box. When we opened the box, there was a USB dongle inside that had the source code for the engine.
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There was one condition though, that Kojima Productions doesn’t just use the engine, but that we develop the engine together with Guerrilla Games, that it should be a collaborative effort. So we were really blown away by their stance on this and being so open with the engine and we thought “Wow, these are the people we have to work with.”