Super Smash Bros. Brawl/Samus
In a nutshell
She is currently ranked 33rd on the tier list, due to the huge nerf to her projectiles and KOing power from Melee, resulting in poor matchups against most characters. All in all, Samus can be a character of good and bad situations with her wide array of projectiles and a fairly powerful spike. A huge problem in competitive play is that Samus is easily chain grabbed due to her heavy weight and large size with the exception of chain grabs that are ineffective on very floaty characters, and can be infinite chain-grabbed by King Dedede. Finally, given Samus' problem with KOing and opponents' difficulty in KOing her, high-level matches involving Samus can tend to take awhile, making time limitations in a match a crucial factor as well.