What is your favourite game?

That depends on what kind of games you play and what platform.
Me personally, I play on PC, my fav game changes from time to time.
As of right now I can say my fav games are Factorio, Oxygen Not Included, Payday 2, Rust.
Now if you asked me what my fav series, I would say anything Zelda related. I'd bought a switch just to play Breath of the Wild.