The Good: Good story, fun gameplay, excellent visual presentation, very catchy music.
The Bad: Very linear exploration, catching only Shadow Pokémon feels limiting, battles wear on for too long, Jovi.
There have been as many Pokémon spinoff games as there have been actual Pokémon games. The general consensus of them is pretty… meh, but there are some good ones. For example, Pokémon XD Gale of Darkness.
In this game, you play as… well… yourself. You live in a big lab with your mom, a professor guy, and your REALLY annoying little sister named Jovi. (I hate her so much. She is probably my least favorite character in all of gaming right now. She is so annoying! Why? Because she always thinks she's right and talks in first person like a little baby! SO RUDE!) Anyway, a group named Team Sipher comes and kidnaps the professor and you realize that there are Shadow Pokémon about. Shadow Pokémon are Pokémon with their souls possessed by darkness (It sounds very Kingdom Hearts, doesn't it. That's because it is.). Your mission is to rescue the professor, save the Shadow Pokémon, and stop Team Sipher from their evil shenanigans. You know, as far as Pokémon stories go, this one isn't half bad. It's got twists and turns and is a little dark (It's about a Kingdom Hearts level of dark). This Pokémon game has the best story out of all of them in my opinion.
The gameplay is still the turn based RPG stuff we all know and love. It's still as entertaining here as in any of the other games. What makes them even better are the Pokémon themselves. They look really good, they have fluid animation, and you really get to see them use their moves. It actually looks like the Pokémon are doing all these things and not two Pokémon standing at opposite fields while certain animations happen between them. No, it goes to a more epic, realistic scale and I like that. Only complaint though is the length. Later in the game, battles start dragging on. Because of these animations, battles seem a lot longer than they should be. If they shortened the battles some, it would be great.
The presentation is great. The graphics are beautiful (for the gamecube, that is), the colors are bright and vibrant, and music is excellent. My favorite thing about the game is the music. No matter what place you're in, you're going to be humming along or tapping your foot or just embracing it. It's awesome. I also like the level design of these places you go to. No two areas you visit feel remotely alike so I like that. Some places are more creative than others, but that's not a big issue.
Do you know what is an issue in the game? The serious lack of adventure. In other Pokémon games, you are free to travel whenever and wherever you want (depending on how many badges you have) and you really feel like you're on an adventure. This game doesn't have that. Exploration feels very linear. Instead of running from place to place, going through grass and fighting trainers on your way to your destination, you go to a map, press A on the place you want to go, wait a few seconds, and you're there. Where's the exploration? Where's the adventure? The other games have more freedom on where to go and this game is just mapped out to you, taking you from point A to point B. This makes it lose its magic.
Now we go to a point in the game that is both a hit and a miss: the Shadow Pokémon. They are a hit because of their uniqueness. Having Pokémon with their hearts possessed by… demons or whatever is really cool. They have these shadow moves that attack opponents by using darkness. They take up no PP and do a lot of damage. Those are fun to use! I also like the process of purifying them. You fight with them and their shadow gauge (the meter that shows how much darkness is in the Pokémon's hearts) goes a little bit down. Eventually, it will enter Fever Mode and start hurting itself until you call its name, forming more trust. You clean their hearts at a relic or in a machine at the lab (which can hold all your Shadow Pokémon and clean their hearts, making things a whole lot easier) and they will become good guys. They will also learn an entire new move pool and you can nickname it! Yay! Those are definitely hits with the Shadow Pokémon.
The miss is that Shadow Pokémon are the only Pokémon you can catch. There's no grass to run through to catch new Pokémon. You can only catch the evil ones that belong to other trainers. Because of this, choosing your team feels limiting. There's very little freedom in which Pokémon you want to use. It feels very mapped out, like the exploration. Yes, there are certain areas you can catch wild Pokémon, but there are only three of them. It still feels very restrictive.
Overall, I think this game is good, but it has so much potential to be even better. As much as I love the gameplay, the visual presentation, and the music, certain missteps prevent it from greatness. As it stands, yeah, it's good. It's fun. If you're an avid Pokémon fan, then you should definitely check this out. If you're an avid RPG fan, then you would enjoy it too. It's definitely worth picking up.