delta5 :
TDHBP_Messed :
You want a mature-adult or a mature-teen game? Like how mature you want it to be?
Mature like XCOM, Final fantasy 7, Shadowrun, ect.
Like violent-mature... ah! Here's a list:
The Elder Scrolls Series
Diablo Series
WoW (it's kinda ironic that people call it WoW when it doesn't wow most of its players!)
Mass Effect Series (I have a feeling that the new Mass Effect isn't going to be really good)
Fallout Series (you tried Fallout right?)
The Witcher Series (I'll just keep spamming "Series" xD)
Dark Souls Series
Star Wars : The Old Republic (you will be able to play if you have a time machine)
Dragon Age Series
South Park : The Stick of Truth
Let's see, 1 2 3 4... 7! I mentioned the word "Series" 7 times!
You know, you could just google them. I googled all of these... Fallout is my favorite if you ask me.