Marth and Roy are both from the Fire Emblem series but are in different games.
Marth is in:
Fire Emblem: Ankoku Ryuu to Hikari no Tsurugi
Fire Emblem: Monshou no Nazo
Fire Emblem: Shadow Dragon
Fire Emblem: Shin Monshou no Nazo - Hikari to Kage no Eiyuu
while Roy is only in Fire Emblem: Fuuin no Tsurugi. He is seen in the secret ending of Fire Emblem: Blazing Sword as well.
Also, both characters are in Fire Emblem Awakening, but only are available as add on content
No, Marth and Roy come from separate Fire Emblemdimensions.
First unlock marth to do that beat classic mode on any mode with 13 of the original characters defeat marth to unlock him then use marth to beat classic mode roy will appear defeat him to unlock him.
No, they do not since they are not even in the same game.
No. Marth and Roy aren't brothers. It is almost impossible for them to be because they are the princes of two different places, and they have different fathers and other relatives.
unlock marth then beat classic mode with marth beat roy.
to unlock roy-finish the game in classic mode as marth and defeat roy to unlock him to unlock marth-use all 14 original characters at least once in classic or adventure mode then finish the game with one of them and defeat marth to unlock him. Alternatively play in versus mode 401 times then defeat marth to unlock him. if you have any more questions about super smash bros just ask and i will answer for you
In SSBM, you have to beat him with Marth after you finish classic with Marth.
First unlock marth to do that finish classic mode with 13 of the original characters then defeat marth. Finish classic mode with marth then defeat roy.
Use Marth on Classic or Adventre then beat Roy just a reminder you have to unlock Marth too
In order to unlock Roy, you must complete classic modewith Marth (it can be very easy difficulty).
The main difference between is that Marth and Roy are princes from two completely different games and universe in the Fire Emblem series.
First you must unlock Marth by finishing classic mode with 13 of the original characters then defeat Marth now finish classic mode with Marth to challenge Roy defeat him to unlock him.