For reasons unknown to this writer, Mega Man's Soccer (alternately known simply as "Mega Man Soccer") has its fans. It's a neat idea, following in the idea of "what other genres can we place our mascot-ish character into?" But as for the execution? Well, it's no Mario Strikers (though we'd love to see Next Level take a stab at a sequel). That aside, it appears that there have been a number of secrets uncovered over the years, thanks to diligent people who have tinkered away at peeling back layers of the game's code.
Ever wonder why there were no credits? Turns out there were!
Ever pondered why it only allowed two players? Well, it seems they originally planned for four!
Issues such as a lack of ending or credits, and the odd inability to play as Dr. Wily despite his appearance on the character select screen have led people to theorize that Mega Man's Soccer had been rushed to market as an incomplete game, and the findings made by The Cutting Room Floor would seem to corroborate this notion. For a further analysis of these findings, check out this article over at Protodude's Rockman Corner.
Will we ever get to see a full, complete version of the game? It's hard to say; perhaps if Capcom releases another Mega Man collection and decides to include it, they'll see fit to finish what they started. Of course, there will need to be a collection for them to put it on first.