Run as far as you can in an infinitely generated level. Every game will be totally different.
You have 30 seconds to collect as many coins as you can, if you get 50 coins you can buy powerups like the iconic fire flower. For every enemy defeated you will be given 2 extra seconds. As you run, you will face more and more dangerous enemies and obstacles, so be prepared!
These are the features of Super Mario Bros: Road to Infinity