Myth
It's easy and fast to create a video game like those you buy in the trade, we can do the same with programs specially designed 2-3. You can also modify existing games to create its own game.
Reality
FALSE
Explanations
Come, see a bit of logic would you like ... If it was so easy to create a game, everyone would have his own and no editor is struggling to break a good FPS! You should know that there is a team of several pros behind a game, which has designed small bits of interesting codes for years, with a budget of several millions and top-level programs!
Moreover, it is forbidden to modify existing games because they are subject to copyright or copyright.
Realty
If you still want to try creating, there are some fairly simple programs that may be of interest: Software to create a video game.
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