|Etemon's skin compared to Metal Etemon's. Note the sunglasses and nut & bolt pattern.|
Even some of the most recent efforts to create a dedicated game modification tool for Digimon World by veteran Digimon hacker Romsstar have turned up no secret methods of unlocking the Metal Banana. It seemed as though this was just one element of the game not implemented for unknown reasons, fully complete and still dummied out. But on one long-neglected corner of the internet, an answer has lied waiting for many years.
one line of text stands out;
Memory cards containing ultra-rare Metal Etemon data for the PlayStation Software Digimon World were given out as presents, among other things.
According to an anonymous user posting on the Japanese-language message board 2channel back in 2006, Metal Etemon was originally a raffle prize given away in V Jump's guide for the game (pictured at right). Raffles of this type are very common in Japanse children's franchises; presumably fans that purchased the guide would mail in an attached slip to get one of the memory cards. The mystery does go a little deeper than this, however. Metal Etemon was not the only missing secret in Digimon World.
There are two other Digimon--Panjyamon and Gigadramon--that are similarly not on the evolution chart, not obtainable in-game, have unused evolution items programmed in, and are likewise fully functional. For years these Digimon have been the subject of rumor, with Panjyamon being conflated with Saber Leomon by the English-speaking fanbase sometime around 2000, and sinking into legend as one of "the three Megas." Such rumors also gave way to later stories of an Electo Ring item capable of evolving Digimon into "Kaminarimon," and of a Moon Mirror item to evolve to Were Garurumon. (Were Garurumon was later proven to exist as an arena sprite, with no proper skeleton, skin, or technique list programmed. While the Electo Ring appears in the game, Kaminarimon is only named, with not even an arena sprite appearing.)
The existence of Metal Etemon, Gigadramon, and "Saber Leomon" was seriously doubted by fans unable to replicate the rumors, and as the years have worn on more recent walkthroughs and FAQs dropped their names entirely, not even making reference to the Metal Banana, Giga Hand, and Noble Mane evolution items. The Digimon (barring Saber Leomon) do exist, taking up the slots in the game's data structure immediately after the last normal Digimon (Mega Seadramon) but before the arena-exclusive Vamdemon and NPC/enemy-only Digimon. Panjyamon's and Gigadramon's level of completion is much greater than that of Were Garurumon; since they're reskins of existing Digimon, these two aren't missing field animations in the way that Brachiomon or Mugendramon are.