Alright, I just would like to point out that Luigi is a coward. However, he is not in any way weak. Luigi is the only one who can hold the power of the chaos heart properly. Luigi, in fact, has more of a chance against Shadow than Mario does.

Luigi can jump higher, and is faster than Mario as well. He can take more than Mario (in the M&L;games he has higher defense and HP.), and is better at dodging. I haven't even covered his attacks and I've already explained in part how he stands more of a chance.

1: Luigi is hesitant to use a power he cannot control. Luigi is, in fact, extremely powerful, but usually does not use a technique until he's perfected it, unless in danger. He can control lightning, throw balls of fire (not his favorite attack, but he can do it), control the wind to an extent (he can make tornadoes around small projectiles and himself), he can do a jumping punch that launches himself fifty feet in the air, and does his opponent a ton of damage. He can produce a field of energy that more or less renders an opponent immobile, though it takes a lot of power. Luigi has also been shown to turn invisible (and nonsolid) with a small amount of extra power. He can also launch himself like a missile.

Luigi, I think, is more powerful. If they each had the same advantages (doesn't shadow carry something around to do his attacks?), Luigi would win.

Luigi would win, I think. He's scared of many things, true - but abilities and bravery are two very different things. For the mushroom kingdom, Mario has average abilites, and is just brave. Luigi actually has some powerful abilities to his name, such as warping space and time (He's been shown to be able to create a vortex, slow down time, manipulate gravity... You get the idea), as well as use multiple elemental attacks, most notably, his electric attacks are rather strong, yet he can also use wind, fire, and plant attacks.

You people SERIOUSLY underestimate the man in green.

Oh yeah, on the subject of Shadow's chaos attacks, Luigi has an advantage no one else has. I'll let you try and figure it out yourself.