I have written in the past about how I feel that Limbo and especially Inside are truly tremendous games. Developed by the same studio, Playdead has proven that you don't need a massive production team to make an amazing gaming experience.
Both of these games have no spoken or evident story and it is up to you, the player, to determine what the hell is actually going on. It is because of this reason as well as excellent control mechanics, that both of these games are easily worth more than $10 each, but for now (and just a few more days) you can get both of them for a mere $7 total.
Both games are puzzle / platformer games and at least for me, this is one of the best game types out there. The problem is that it is so difficult for people to get the genre "correct." There are a ton of platformers out there, but a vast majority of them absolutely suck either because the controls are unresponsive / broken, or because the studio focuses too much on having amazing graphics and too little on the game actually being fun.
Limbo came first and is significantly more difficult that Inside. Perhaps this is a big part of the reason why I enjoy Inside so much more but still feel as though Limbo is still one of the best puzzle/platformers ever made.
The story unfolds in such a way that there is no real story that you are aware of - there is not spoken or written dialogue in either game and it is completely up to you to determine what the story actually is. This doesn't mean the games are confusing because of this, it just means that they do a great job of "kinda" telling you the story without spoon-feeding it to you. I love a great story, but I easily tire of excessive dialogue either written or spoken. Therefore, the fact that neither of these games have any of either is a true godsend.
Both games are extremely creepy and have a wide-variety of gruesome ways of dispatching you. The tension is kept on although there are plenty of autosave spots so its not like you are going to be backtracking a ton and repeating the same tasks over and over to the point of boredom.
Both "stories" have never been explained by the makers of the game and as a result there are hundreds of videos out there with theories about what is going on as well as some serious easter eggs included (especially for Inside) that has some video creators spending more than an hour postulating about what the story actually is. Some of these clues that these sleuths have discovered are so subtle that I didn't notice them at all when I was playing but once revealed to me it all kind of made sense.
I bought both of these games when they were around $15 each and both were well worth that price, but the fact that you can get them both for $6.99 right now is just outstanding. I highly recommend that you do so if you have not gotten a hold of these games already.
If you have never played these games I actually envy you because now you can get both of them for the price of a McDonald's value meal and honestly, of all the game purchases I have made in the past 5 years or so, both of these are some of the best. There's never been a time like the present to get them and they are not featured very high up in the list on the sale section of the PlayStation store, so you may have to use the search function in order to find them.
Highly recommended. Tick tock though! In a few days the sale will be over!