I'm working on MarioRL right now as my entry in the annual 7DRL contest. 7DRL is a programming competition that takes place annually. The goal is to make a finished, playable Roguelike (aka dungeon crawler) game in 7 days.
There aren't any actual prizes or places. If you finish your game in the allotted 7 days, you're a winner basically.
There are a lot of great roguelikes based on other games such as DoomRL, CastlevaniaRL, ZeldaRL and so on. I realize a Mario themed anything isn't incredibly original but it hit me this weekend that no one has ever made a roguelike based on Super Mario Bros, a game ripe for rogueliking. I mean, you travel through various dungeons, fighting monsters trying to rescue a princess. A little cliche sure but perfect!
I'm using GM:HTML5 which I just purchased last week so I'm not sure how great of an idea that was but I'm rapidly learning the GML scripting language. GM:HTML5 does have drag and drop game creation but for something like a roguelike game you definitely have to use the scripting language.
It's similar to Java or C++ in a way and while I'm no expert in either, I'm picking it up fairly quickly.
With any luck, I'll have a playable game by the contest's deadline and once that's over, I'll take my tune polishing and fine-tuning it.
And of course, here are some screenshots: