Pikachu. It has a high attack, good against bosses (Excluding Skarmory) and it looks pretty cool. The downside is it learns moves S-L-O-W-L-Y. Plus Groundon has a fairly short temper with electric types... If you're in MD Explorers of Time/Darkness or sky, Chimchar always works for me. Just watch out for that Groundon.
Riolu, Phanpy or vulpix
Has to be Blue, In my opinion.
I guess it depends which Pokemon you think is best. There are an equal amount of advantages and disadvantages for each possible combination of starter Pokemon in mystery dungeon, there is no such thing as a "best pair."
It depends on what you like. Every Pokemon is different.
squirtle and pikachu will be the best
garchomp and altaria or charmander and mudkip
I think its charmander and riolo
there isn't one. but for explorers of the sky, a lot of people would say riolu, but hes rubbish.
The best Pokemon you can get is mew. or you could get something in buried relic mew is in there
Pikachu because it can learn discharge if you are a pikachu choose chimchar.... I love you kristin toedtman of bloomingdale NJ
Youtube would be the best
Totodile, with partner of Torchic