A game that doesn't cater to children and can have a difficulty that isn't super easy. Such as dark souls.
"such as dark souls"
git gud
Let's say I made a game about bubbles, kittens, puppies, and everything you'd call catering to children, but incredibly hard. Would you call that mature?
Let's say I made a game about wrestling with manly creatures such as hydras and bears thats ultra violent, but incredibly easy. Would you call that mature?