What is a game that you can beat many times and never get bored?

[BluBird]

Mega Man X.

I've beaten it so many times, and have come close to beating the speed run record. It's the kind of game that I can play only lazily aware of what's happening. Whenever something devastating happens I actually play this. It gives my hands and the back of my head something to focus on while I go over more important things. It helps me focus, really.

 

[Mika]

Portal and Portal 2 are the only games I could ever give more than a second playthrough. Even if I pick a completely different path in other games, I end up getting bored. I've played Banished dozens of times, but I don't think it actually has an end.

 

[teamshepherd]

Probably any of the Sonic games, I think I could play that all day every day

 

[fire421]

Metroid Prime, I beat that game three times and still enjoy it. The atmosphere, gameplay, and music were near perfect in my opinion and that is what keeps me coming back to it. I also loved Paper Mario The Thousand Year Door but Metroid will always be my favorite.

 

[Kamarsun1]

Mine has to be Paper Mario: The Thousand Year Door for the Gamecube, I can beat that game an infinite amount of times and never get bored, I just love everything about it, it's the greatest Paper Mario game in the series in my opinion. Everything about this game is excellent, I love the story, the gameplay is fun, the graphics, art style, and humor of this game is unique. I specially love the train chapter because of its nice ambience and how everyone is scared of the ghost that habits the train. This is a game I will always admire!

So, what's yours?

I would have to say Super Mario Bros. I seem to find something new each time I play it. From the old ones to the newest, Mario was my favorite as a child, and I still like the Mario games.

 

[Heliocid]

For me it is the Mass Effect trilogy. I've completed it numerous times, each time with diffrent class and diffrent choices. For some reason there is a special place for these games and I love coming back to them.

Other games that come to mind are Binding of Isaac, Binding of Isaac: Rebirth and FTL. I'm a big fan of roguelikes. The fact that I can just pick them up at any times and spend half an hour trying to beat randomized dungeon makes them hard to hate.
Speaking of randomization, many people dislike that in some games you need to relay on RNG to such big extent, but for me it's another great feature. It won't always be fair and sometimes will make me angry, but if not for it, those games would loose their charm long ago.