In this story you play as a Pokémon (mainly a starter or another small Pokémon from Generations I-III) who has no memory of who he/she is, only that they were once human. Your partner Pokémon and yourself are decided through a personality questionnaire you play in the very start to help you begin your adventure. The game's main intention is to have you and your partner go out on adventures and quests where you venture into Dungeons to rescue fellow Pokémon who are lost. One recurring theme is that your character is plagued by mysterious dreams. What do they mean? Why are you inflicted with them? You'll have to play on to find out!
The dungeons bring a whole new perspective to playing Pokémon. Each dungeon has a different layout and requires you to explore every nook and cranny. The dungeons are filled with aggressive Pokémon who will attack without reason, so you must train and endure as best you can if you want to make it out alive. The main objective is to search every floor looking for the blue stairs icon which helps you ascend/descend further and help you search for your objectives. The top of the screen shows you and your team, whilst the bottom shows a silhouette of the dungeon map - as you venture further, the dungeon's layout will begin to write itself. You'll encounter territorial Pokémon as well as discover things in every area. Once you have reached your objective, you and your fellow Pokémon will shine a Rescue Badge and you will all zoom out of the dungeon. Strangely it looks like an abduction or like they're shouting "It's Morphing Time!"
Thanks to the cataclysmic ending, things become out of balance and new things arise for you to fix and discover. Evolution becomes available which is very interesting as it's not like in the original games where you suddenly begin evolving after a battle. No; in this game you use a mysterious stone, similar to Pokémon Coliseum. Plus a whole new load of epic and frustratingly difficult dungeons become the bane of your skills. To make the game harder than before, these new dungeons have hidden traps everywhere that affect you in the most annoying ways, really putting your skills and patience to the test. Some traps make your Pokémon or Items become damaged or inflict problems which can make it harder to advance. On the bright side, you are now able to recruit new Pokémon from the dungeons to join your Rescue Team and come back to other friend areas (so long as you have purchased them from Wigglytuff). So why not recruit Legendary Pokémon and make your team look overwhelmingly powerful and cool? I'd say the biggest problem that gets me every time besides the damn traps are the Monster Houses. Imagine walking into a room where suddenly a big group of powerful Pokémon fall from the ceiling and the music suddenly changes which means you're pretty much screwed. Seeing as they surround your team, they're pretty much unbeatable. I've lost lots and lots of times thanks to this mechanic. If you can somehow overcome this surprise attack then well done! Otherwise stock up on Revival Seeds and expect the unexpected.