They know what is going to happen.
Time to sue!
Depends which German company. They have really good ones.
Ubisoft and Terraria? Well, that would be terrible, if you look at their Assassin's Creed games or Far Cry. You would pretty much see new, overpowered additions that would make the game too easy, while gameplay wouldn't change even a bit. And new Terraria parts would be released every year, because if Ubisoft Germany claimed it, it would of all Ubisoft's.
They would probably turn it into a soulless demake of itself with fancier graphics.
That's what they do to sagas not started by them.
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