Mine I put it together myself.
- The background is one of the end backgrounds of The Future-Past 3 DLC of Fire Emblem Awakening.
- The pixel art is made by Daniel "Abysswolf" Oliver. Of course, they are three characters appearing in Super Smash Bros for Wii U and 3DS, and my actual in-game "mains". They can be seen alongside more of Abysswolf's work here:
http://kotaku.com/smash-bros-characters-turned-into-gorgeous-pixel-art-1682254842 - The sprites were ripped by various rippers on The Spriters Ressource, and recolored by me.
From left to right, we have Little Mac (boxers with green gloves, from the Punch-Out!! games, has his victory sprite from the NES Punch-Out!! game recolored in orange, bronze-like colors), Mega Man / Megaman (self-explanatory. I expect everybody on this site to recognize him easily, for various reasons. He also has that gold sprite that I believe most people here would recognize as similar to the one that appears in the ending of the Megaman 6 chapter in Megaman 8-bit Deathmatch, except it's the idle sprite and it's colored WAY lighter, because I recolored him myself), and Lucina (swordswoman and lord from Fire Emblem Awakening, and she's also a time-traveller. Her "overworld map"s idle sprite from her own game has been recolored by me to be somewhat monochrome and silver-like).
You might recognize the recolored sprites from here, if you've seen me before (on Smack Jeeves):
http://extremmefandumpsandbox.smackjeeves.com/comics/2117216/smash-4-wiiu-3ds-top-5-newcomers/