UnMetal.
I'm about half way through(glacing at a guide) and I'm enjoying it. It takes a little while to take off but it's very much a love letter to the early Metal Gear games(notably the NES/MSX 2d ones) without being an explicit rip-off(Okay, it's very obviously supposed to be Metal Gear but without IP rights but it's also firmly a parody).
Basically, Jesse Fox is framed for a crime he didn't commit(and is arrested by soldiers who say "We're arresting you for a crime you didn't commit" in the intro) and is tossed in jail in a military base...somewhere. He escapes and the apparent goal of the game is to escape from the enemy but also find out of about the mysterious "Project Jericho(or Jerico, as the game spells it)". It's divided into linear stages, and once you complete one you can't return to an earlier one that I can tell) but you get a fair bit of leeway to explore within those stages and find ways to bypass obstacles and deal with guards.
It works fairly well and the game is decent about hinting at how to deal with certain obstacles(via radio calls ala Metal Gear) or just giving you a hint when you die(and you will die). There's a fair bit of scrounging for items to bypass traps and obstacles, and weapons to allow you to deal with enemies(like you need a pistol to deal with at least one boss you encounter). In one section you need a flamethrower but because the flamethrower has been repaired in the field with stuff you've found, it overheats very quickly so you can't just spray forever and have to use it in short bursts to allow it to cool. Overheating it causes it to explode and instant kill you. And this becomes really interesting when you fight a boss with it later because want to take advantage of when the boss is vulnerable to fry it, but you also don't want to kill yourself with the flamethrower and the boss also summons rat swarms you also need to use the flamethrower to burn. Also, it doesn't seem like you can leave a stage without getting the required items to proceed later on but you can miss some optional ones(like more bullet capacity or a health boost).
There's a boss or two per level and most of them require different tactics to deal with. Luckily when you die you restart from just before to began the boss fight so you aren't trapped by it,and you can skip the dialogue that plays out each time you start a battle.
Probably the most interesting thing the game does is set it up as Jesse telling the story to an interrogator(and also his girlfriend at a presumably later date, which is weird) and there's a sense that there's a (very) unreliable narrator at work here. Since Jesse is telling the story, certain things won't appear on screen until he explicitly mentions them and in other bits, he'll be asked a question about a certain thing that happens and the player is given a choice what he says, which changes what happens on screen. Sometimes this can make the encounter easier or harder depending on how you answer, sometimes it's just flavor text. The game knows you'll notice this eventually and will eventually fuck with you with it. For example, one boss is a trash squid thing that initially doesn't attack. After you damage it enough, you're asked if it had tentacles and are given a choice of 3 numbers(2, 4 and 6)Choosing 6 means the monster has 6 tentacles and is actually easier to fight, while choosing 2 means it has 2 DOZEN tentacles and thus much harder. I found that clever if not slightly annoying.
Jesse also comes across as a bit thick a times, which makes you wonder just how much of this is real, among other things. At one point he finds a truck to hopefully escape with, and looks at the engine to see if it works. He then says "I realized I couldn't use it. It had a diesel engine and using it would pollute the air, so I'd have to find another transport method". I appreciate jesse's concern about the environment but it does feel like a convenient excuse why he couldn't just escape right then and there(and he'll eventually try to stow away in the back of a different truck, only to be thwarted in his attempt). Jesse is doing a decent Solid Snake impression and while the sound and art is a little amateurish, it's an indie game and I'm willing to cut it slack because it's consistently amusing(though how funny you find the jokes is totally subjective). It also seems to get what made Metal Gear fun on a gameplay level and plays to that, but doesn't attempt to replicate Kojimas long winded feelings about...well, lots of things. This is probably for the best because trying to parody Kojima there, would be....I'm not even sure you could do it.
Added:
I'm getting closer to the end and it's definitely hit its stride. The plot still isn't particularly good but it's serviceable. Tell me, children, what do you think the core component of the Bad Guy's evil plan is? Spoiler: It's a Nuke. It's always a nuke. And for what this is making fun of, that's totally fine to drive the action. I'm waiting to see if there's a mech waiting at the end of this to go with the aforementioned nukes.
I'm kinda digging some of nods to Metal Gear, including one bit where a guard says "I feel Asleep", which prompts Jesse to call out "It's 'I feel sleepy!' " to which the guard corrects himself and then falls asleep. There's also a amusing bit where you walk into a room, hidden from view, where 3 guards are all playing DnD on duty and when they hear you, they think it's their boss coming to check on them and all hide in Cardboard boxes. Cheeky.
The Boss fights do prove to be varied and interesting, all involving a puzzle of figuring out the proper way to fight them. Ironically none of them take that many hits to take down and done correctly each boss fight can be over in 2 or 3 minutes, but that's assuming you're doing things right and likely you'll die a couple times figuring that out. But since the autosave is always just before you initiate the boss fight(so you're not trapped in a death loop) you can easily either go back to get more supplies or can easily pick up from the beginning and try the fight again fresh to get it right this time. There's also an amusing bit where you get into a "boss" fight with a nasty drill sergent where you're picking the right lines of dialogue to defeat him(but if you pick the wrong ones you die) in a rather weird manner. It's trial and error but it's not that crazy and being able to skip dialogue you've already heard makes the repeat rounds go faster. The punchline is that whoever says they're from Texas loses the fight, because only two things come out to Texas.....Propane Accessories and Assholes
It also has one of the more interesting save/quicksave methods I've seen. Aside from Autosaves, which happen at key parts of the game, you save manually by going to a Restroom/WC and using the urinal. You can also find little portable potties that go in your inventory, and those act as quicksaves. However, you can only save when you're in a safe spot and when using a little porta-potty, it fills up with pee and has to be dumped in a WC before you can use it again, and if you quit before dumping them, you lose them apparently. So that's interesting.