The Ruin is a one-level hack about as long as you'd expect a castle towards the end of any full hack. It's full of custom graphics, both "Redrawn" and Supertails-style, and consistent in that regard. The hack uses a translucent red gradient HDMA effect in most rooms, which causes some weirdness between rooms because you'll see a black screen with the red fade.
The design quality itself is excellent and has balanced difficulty. The level is action-oriented though there is one spot you have to go out of your way a little to grab an item and it's camped tightly by a nasty Thwomp. Some areas will spawn throw blocks so you don't worry about limited chances at getting through areas where it seems like otherwise you would be able to screw yourself.
You'll see walking candle flames like in SMB3, you'll see flame pillars jump up from lava, and an all-new boss at the end who spits fire at you. The boss is pretty easy since you can use the terrain to dodge his fast flame and you can duck at the spawn point of the throw block to easily dodge his spiraling flame while you grab your ammo. The only danger in that is if you jump up as he uses his fast flame because he's almost guaranteed to hit you in that case so you have to make your timing count. Still, it's fresh and different.
Purposeless is the mushroom because the hack actually uses coin-based health, exactly like Sonic's ring health... I can't understand why that was left in this hack. I also don't get why that red bar was left in place of Mario's name.
Overall, good hack and I don't get why it wasn't accepted during remoderation.