Mario Mario. Let's see, we've got Super Mario Sunshine (this should by itself beat Luigi any day), Super Mario (I don't see Super Luigi anywhere), Super Mario 64, Super Mario Galaxy, Super Smash Bros. Brawl (yeah, he kicks Luigi's butt). The list goes on and on.
Luigi Mario. Let's see, we've got Luigi's Mansion (this should by itself beat Mario any day), Mario is Missing, Super Smash Bros. Brawl (yeah, he kicks Mario's butt). The list goes on and on.
They both are really great.
What the...? If we are going by games as this list implies it is obviously Mario who is cooler. Super Mario Galaxy alone is enough to establish this and Super Mario Galaxy 2 pretty much makes this a fact. Even without the games, Mario to me is way cooler than Luigi.
He's faster, jumps higher, has a more well established personality, and ISN'T a maniac (see game theory's "Mario is Mental" series https://www.youtube.com/watch?v=7WMSQNVhMqA ). Plus he got his own year! It might be the hipster in me talking, but I take player two, any day!
He has a better personality, looks and powers. Mario is an arrogant bully. Enough said.