Pokémon Rumble
Pokémon Rumble is a simplistic beat-'em-up-style adventure focused on collecting and battling toy Pokémon. Unlike the 3DS entries, there isn't much of a story here, but that just helps to keep it focused, and the game isn't long enough for the omission to really stand out. Instead, your goal is to recruit strong Pokémon in the hopes of winning successively more difficult battle royale competitions to progress through the ranks. Each new rank you reach unlocks its own set of six stages, and to recruit the best Pokémon, you'll likely need to challenge all six of them.
The stages are straightforward, with each of the six following the same general structure, but featuring a different environment and selection of Pokémon. Every stage chains together a few linear rooms to fight mobs of Pokémon in, followed by a boss fight against a goliath Pokémon. Every Pokémon you knock out as you progress through the stages, including the boss, has a chance of tipping over instead of disappearing, allowing you to collect them and add them to your team. If you're lucky, they'll have high stats, good attacks, and maybe even a special ability.
As the Pokémon you collect are toys and not actually living things, they can't get any stronger, so you'll need to focus on recruiting if you want to be strong enough to progress. While I normally enjoy strengthening my Pokémon, this approach works well for Rumble, constantly forcing me to adjust my strategy to match my new Pokémon's capabilities, keeping an otherwise very repetitive adventure feeling fresh. Repetitive is still an appropriate description though. Other than different pools of Pokémon to fight and befriend, all nine ranks and their stages are almost entirely identical. The only other standout difference between them is the battle royale.
In order to rank up and unlock the next set of stages, you'll need to join a battle royale of powerful Pokémon and come out on top. These challenges have a minimum power-level requirement, so you'll need to recruit at least a few Pokémon in each rank before you can continue. They are also time-limited, so you can't cheese the battle and just let the other Pokémon defeat each other. Each Pokémon you deal the final blow to will also add some time to the countdown, encouraging proactivity in the ring. I never preferred these battles over the regular stages, especially since they don't allow you to recruit any Pokémon, but they did offer some difficult fights against some very powerful opponents, which were hard to come by otherwise.
Despite the relative ease, simplicity, and repetition, Pokémon Rumble was more than my little Wii-Shop-browsing self could've ever hoped for. I'm sure that nostalgia is responsible, at least in part, for my enjoyment of this delisted spinoff, but I had a great time with it. I was especially blown away when I thought I had beaten the game, only to find out that I had just hit the halfway mark, and Sinnoh Pokémon were joining the previously Kanto-only cast! For a small, download-only title, Pokémon Rumble has a lot to offer, especially if you are looking to complete it. Unfortunately, the whole series is no longer obtainable through official means (used physical copies notwithstanding), so all we can do is hope for a new one to come out soon.
Although the game is no longer being distributed, you can learn more about it here (as of 4/21/23): https://bulbapedia.bulbagarden.net/wiki/Pok%C3%A9mon_Rumble
