You&#x27;d be surprised. There&#x27;s a GDC talk about Antichamber from a couple years ago (I really recommend watching it) which explains the amount of time that was invested into the game.<p>Antichamber was a 7 year long hack on Unreal Engine, it&#x27;s <i>really</i> not a drop-in game.<p><a href="https:&#x2F;&#x2F;www.youtube.com&#x2F;watch?v=wOlcB-JxkFw" rel="nofollow">https:&#x2F;&#x2F;www.youtube.com&#x2F;watch?v=wOlcB-JxkFw</a>