Mew2
Sex is overrated
I agree with EonX Rosalina has a pretty unfair advantage with Luma. I hate to be the type of guy who calls things broken but basing in the results of tourneys and matches I have had Rosalina is the best character in the entire game and a bit broken IMO. While killing Luma is a good option (still takes time and you'll get damage) Rosalina isn't useless without Luma and will get a new one after a while.
In a sense I see Rosalina in Smash Bros like Mega Kanga in Pokemon XY; having a second character is pretty dam good and while it isn't as powerful as Rosalina (or mommy kanga) it still gives you a superior advantage over your opponent and before you start with "Oh but Ice Climbers..." remember that when Nana didn't respawned like Luma and that Popo alone was way worse than Rosalina alone.
In a sense I see Rosalina in Smash Bros like Mega Kanga in Pokemon XY; having a second character is pretty dam good and while it isn't as powerful as Rosalina (or mommy kanga) it still gives you a superior advantage over your opponent and before you start with "Oh but Ice Climbers..." remember that when Nana didn't respawned like Luma and that Popo alone was way worse than Rosalina alone.