This game is a Mario clone that is free and open source. The game is surprisingly like the old Mario NES games. After each level of obstacles, varying from the deadly mushroom people to the scary living flowers with faces, you will advance to the next level. The only thing, however, there doesn't appear to be very many levels. I think there is around 10 to 13. But, once you finish the game, the fun doesn't end...
The game has a built in level editor, so you can create super hard (or super easy;-) levels. Also, since this game is Open Source, you are allowed to modify it, and this game is pretty easy to "customize" if you want to. If you look for the "pixmaps" folder, you will see every graphical element to the game, and each of these you can edit! It seems that the purpleish color stands for transparency. So, what are the possibilities of this you ask? Well, the possibilities are endless! You could make the flower creatures be someone's head, or you could have Mario be a dog, or you could even replace the "Super Mario" title pictures with "Cybernet Resources"! So what are you waiting for? Go and start downloading it;-)
P.S. There is one other really cool hack you can do. Find your .sav file in the saves folder after saving a new game and exiting the program. Open that .sav file with your favorite text editor, and you can change what level you are on, change how many points you have, how many gold pieces you have, etc. Have fun:-)