Quick background lesson: Megami Tensei is the Japanese RPG Ã¼ber-series that Persona 3 belongs to. If that name doesn't ring a bell, that's the one where you control a team of high school students who activate special powers by... how do I put this gently... pressing a gun to their own head and pulling the trigger. It's a combo move so blatantly insane that even American children have yet to kill themselves trying to replicate it, and most of our hospitals now have entire wings devoted to Stone Cold Stunner victims. Now that you know Megami Tensei is actually Japanese for "brain problems," let's look at their entry into the happy-go-lucky pocket monster market: Devil Children.
Like Pokemon, it came in multiple versions (Red Book and Black Book), and like most Game Boy Color games, the graphics came with a free case of eye-bleed. But unlike Pokemon, here you gain monsters not by battling, but with diplomacy. You and the monster have a conversation, and, if all parties agree, they might decide to join your party. Look here, game: I'm not Kofi Annan. I don't care what the other side wants. I only care about what I want: to beat a wild animal into submission, then trap it into a cage that fits on my belt. And I want that monster to love me for it. Next!
Robopon is one of countless "Pokemon BUT WITH ROBOTS!" clones, and manages somehow to be the most egregious: the final group of enemies is called "The Elite 8," for Christ's sake. Robopon was able to squeeze in a few unique aspects of gameplay, but only in ways that make it needlessly complicated. For instance, Robopons don't evolve automatically. You've got to collect energy balls off of random enemies and return them to a laboratory and have a doctor do it for you. Basically, Robopon is Pokemon without any of the fun. Let this be a lesson to you: If you're going to plagiarize a game, remember to also steal the good parts. Also, don't name any of your characters "Screwy."
History has not been kind to Digimon. Their peaceful predecessor, the Tamagotchi, came out the same year Pokemon did, and the first battle-ready Digimon virtual pet followed only a year later. Digimon shared a few similarities with their fellow "mon" game - monsters, evolution, training, battles... everything except the whole "expand into an out-of-control international marketing phenomenon capable of separating children from their money like shaking loose fruit from a tree" part. It's not really Digimon's fault; they did everything pretty well: pretty popular videogame, pretty popular TV show, pretty popular card game. They did well enough to get by, but one look at the sales figures told the simple truth: Agumon was never going to be roll as deep as that damned electric rat.
Worse yet, they're never going to stop being compared to Pokemon, even though their games have developed in totally different ways: Digimon has always been more about nurturing and raising a single monster than collecting all of them. Digimon are emotionally needy, they have to be praised and punished to guide their behavior. Pokemon are independent, stable. Reliable. Sorry Digimon, but that's what I need in a relationship right now.