Usually smaller scale indie games are the ones doing it, big shot studios feel the need to go ham on graphics. Here's a handful I managed to scrape together from memory and quick searches, but it's easy to find more.
There _has_ been quite a few retro-style, pixelated graphics style games to come out of that sector for one reason or another, but ignoring that, the games tend to have a more stylized feel to them. Limited fidelity means the games need to more creative, but I think that tends to just come with works of passion from smaller studios.
Let's throw in everything Way Forward is doing as well, such as the Shantae series of games.
It's been awhile since I've played a sidescroller that warranted multiple playthroughs, but I picked up Shantae: Risky's Revenge up in one of the HumbleBundles, and I loved the hell out of it.
One part Castlevania, one part Megaman, one part Metroid.
It was so good I went out and bought an XBox One controller to play it further, even though I don't own an XBox One. Side note: apparently its the best PC gamepad you can find that has a good D-Pad; the D-Pad is probably the best one I've used since my childhood.
Oh wow. It's actually plus-shaped. I've been looking for a PC controller with a plus-shaped D-pad for a while. They've been rare for a few years, due to Nintendo's patent on plus-shaped D-pads, but that expired in 2005.
Yup, and I actually had bought a XB360 gamepad... the D-Pad was mushy and horrid, returned it immediately for the XBOne one and it's a well built solid controller.
Also, I don't need to put batteries in if I run it off wired USB, so theres also that.
Been enjoying the hell out of Nidhogg recently. Some other notable ones are Mark of the Ninja and Bastion (maybe? I don't know if you're counting 2.5d games. included it because its absolutely, stunningly, beautiful. seriously worth looking in to)
Nidhogg is amazing :)
My goto answer for addicting 2d game is Binding of Isaac.
I own a bunch of retro consoles and games, pretty much all by Nintendo and have always wondered if there's an interest in "let's play" of an original Legend of Zelda and so forth (I'd guess most are done via emulator but that just doesn't feel right to me :P).
Would require buying a hardware capture device that's Linux compatible but those are 1in the 50-200 Euro range. I'm feeling like it would be something I'd have a blast with but not sure.
Also, all kinds of strategy games. Eg Europa Universalis 4, any Civilization game (even though they may look 3d these days, it's not why you play them).
Re: EU IV, I'd really like to get into it, but the in-game tutorial is very, very bad. I've had several tries over the last year, but always gave up way to soon.
Is there a practical intro somewhere? One that allows me to actually play a game, even losing it badly, but not encounter half a dozen "huh, I have no idea what that means and what I should do now" situations every turn.
You could try some videos as bookwormAT suggested, alternatively (or in parallel) you can just play as one of the easy nations (Ottomans, Spain, Portugal, France, etc) and blunder about. The Ottomans are nicknamed Easymans by the fans.
That's how people learn Dwarfortress, which is even less penetrable. Remember, losing is fun.
I have nothing against losing, but the UI has dozens, if not hundreds of buttons at any time, most very inconspicuous (oh, that's a button?!), and no way to guess what they are for. It's... frustrating.
I'm pretty sure every one of those games except Papers, Please and Hotline Miami, and maybe even those because I don't know much about HaXe or Game Maker, is made with a 3D engine (Unity, XNA/MonoGame, whatever). I mean, you namedrop Sunless Sea, but they do an absolute ton with 3D effects to create the desired look of the game.
Yes, they're made with a 3D engine because the platforms and the widely available frameworks are all 3D. However, the games themselves, the gameplay, and the primary aesthetics of the games are not 3D and would be just as home in a 2D or 2.5D engine and hardware with at most minor changes to the visual look and feel of the game.
These games are fully 3d modeled and in no way a 2d game. Their gameplay may be portable to a 2d platform, but they are not 2d. The is a significant difference in terms of development.
You left out Axiom Verge. Fantastic game in my opinion with really nice looking environments, and all the more impressive considering one guy coded EVERYTHING in the game, including the graphics. The tileset is a pretty accurate tribute to Metroid/Super Metroid
Literally every single game you named was made using a 3D engine. They just went for a 2D top-down view and pixelated graphics,but internally they are all rendered using OpenGL/DX and orthographic cameras.
Well of course, but like I said - the games are made using 3D engines,which use OpenGL/DX to render the scenes. The reason why I point it out is that in both of these APIs if you want to make a 2D game you still operate within 3D space - you just use orthographic cameras and have your Z coordinate set to 0.
This is getting a bit pedantic. Yes, even in DirectX the 2D API was deprecated in favour of 3D one. But the source of a difference isn't the flavour of API you use, it's whether you go full 3D, with polygon meshes, (usually) trying to be "realistic" vs. going with a single perspective and animated sprites.
You seem to be very keen on holding to that OpenGL/DX reference, and I am not fully sure why, it's not relevant to the point I was making. Maybe I should have just said "these games are rendered in 3D space, using 3D engines, and APIs which are used for 3D work normally, so they are not 2D games in the same way SNES games were 2D". Would that be better?
Yes, we get it, but it's still wrong and irrelevant. Not all of those games use 3D engines (Shovel Knight?) and I'm pretty sure not all of them even use a 3D API. But even when they do, they're still 2D games with 2D based gameplay, 2D collision detection etc.
Yep, Indie games are a gold mine for great/unconventional art and design, as well as original gameplay mechanics. Some ones I've enjoyed: Limbo, Thomas Was Alone, Cave Story, Braid, FEZ.