The more content you watch on the internet, the more you'll know that the idea of a Mario parody where Mario's life is all gritty and REAL and DEPRESSING is a WILDLY overdone concept. Watch the first episode of HotDiggedyDemon's Wacky Game Jokez 4 Kidz. In general, with video game parodies, you have to think outside the box at this point or else you'll be making a story that's been done a million times. Obviously people are bound to repeat stories other people have already done every once in a while, but sad Mario is a concept that's done so much that it's something people shouldn't bother with anymore.
Your drawings are pretty good, though! The drawings and texture overlays looked good. Good job on that stuff. The lines were pretty good. You obviously have a pretty decent grasp on good looking line widths and generally keeping the outlines looking aesthetically pleasing for the style that you were going for.
The animation could use a bit of improvement. There's a way to do motion tweens and there's a way to not do motion tweens (look up Andrew Kepple/TMST if you wanna see some really good tween based animation). Like, obviously the part at 0:49 had to be tweened and that kinda stuff's fine, but the part at 1:05 looked kinda bad. It just looks lazy when you're just flipping the image horizontally and adding a little bit of bounce to the tween. It would've looked better if you put the effort into actually using another drawing instead of flipping it.
Also, something that I'm seeing a lot of people do is the "full screen face closeup" thing, like, at 0:39. It looks amateur and kinda lazy and sorta over-used at this point. You might as well just do a normal close up where you draw the entire head out. If you want to create a more intense shot, blur the background and zoom in. Basically, there are better ways to convey a close up with intense feeling.
The frame-by-frame in the first shot was pretty good. One could say it could use more inbetweens, but really it was something that could work on fours or however many frames you held some of the frames for.
I always love darker styled stuff. Like, David Firth's stuff and all that. You have what it takes to make a really cool dark animation, it's just that the idea behind this one was kinda whatever.
Oh, also the sound effect of like, a cinder block being dragged across concrete (or whatever that was, I don't know) was pretty funny at 0:49. IMO weird, almost out of place sound effects are always pretty funny. I liked it and I think it fit well as far as tying to make the audience laugh.
Also sorry about any reviews you'll get that suck. Newgrounds reviewers suck 90% of the time. Just ignore anything that isn't obvious constructive criticism. That's not to say that you won't find good criticism that's formatted like crappy criticism. The review before me could be implying that the dialogue or portrayal didn't carry out as well as you might've hoped. JUST BE SMART ABOUT IT because you kinda have to on here.