Dunno if life is strange is considered least known, it has a pretty big fanbase and was big back in the summer. But I guess it's not known as much? idk but yea that game was amazinggg
I'm thinking old games like Glover...my first game I had is on n64. It's pretty unpopular but very fun.
Favorite game and obsession. Wouldn't say that nobody knows about it, rather everybody kinda forgot. It was successful in reviews and sales, it's just 8 years old with a dedicated, but dormant fanbase.
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As for a game that nobody knows about but is really good how about Deemo? It's a mobile rhythm game made by a Taiwanese company (Rayark). One of my all-time favorite games with one of the most sad endings. ;-;
Has anyone mentioned Another Code: Two Memories for DS? Because damn I cried at the ending. Great graphics and mystery/crime-themed plot, plus very tear-jerking ending (if you play it right). Highly recommended.
I see mention of To The Moon! Very, very great story for an RPG. c:
Looking through my games, I guess Palette (on PC) is worth mentioning? Haven't played through the whole game yet, but it's a sort-of mystery game. Similar with To The Moon, you're trying to unlock a series of past events, but you have your limits and stuff. The gameplay is unique, to say the least.
That's all I can think of at the moment. x)
edit: Oh! I totally forgot Drawn To Life. It's an adorable platform game with a cool story and you can get easily attached to the characters. The ending is also sad and cute at the same time and eeee. I played it as a kid (my cousin had the cartridge and I borrowed it), and it was like the first DS game I got so emotionally invested in.
I always assumed the Sly Cooper series was pretty popular, at least back on the PS2 when 3D platformers were still moderately popular. I never got a chance to play it though. I should really pick up the HD trilogy at some point. The mix of platforming and stealth always sounded pretty awesome to me.
It seems kind of like Jak & Daxter though in that it's not necessarily unpopular, it's just sort of irrelevant now like most 3D platformers, which is a shame. Mario and Ratchet & Clank are practically the only big name 3D platformers I can think of that have managed to stay relevant in modern times, or at least they still get semi-regular sequels.