For innovation and story:
* Pokémon Black and White: Introduced a new region, Unova, with a fresh roster of Pokémon and a complex story focusing on ideals and the meaning of being a trainer.
* Pokémon Sun and Moon: Introduced the Alola region, a unique setting with island trials and a focus on Alolan forms (regional variants of existing Pokémon).
* Pokémon Legends: Arceus: This open-world RPG takes you back to the Sinnoh region's beginnings, offering a new take on exploration and catching Pokémon.
For competitive play:
* Pokémon Omega Ruby and Alpha Sapphire: These remakes of the third generation games feature a refined competitive scene and a new Mega Evolution mechanic.
* Pokémon Sword and Shield: These games boast a strong competitive scene, with new Dynamax and Gigantamax forms adding a new layer to battles.
For nostalgia and charm:
* Pokémon Yellow: This classic game allows players to choose Pikachu as their starter and features a unique story with the iconic character.
* Pokémon Gold and Silver: These games introduced new generations of Pokémon, a day-night cycle, and a vast Johto region to explore.
Ultimately, the "coolest" Pokemon game is the one that resonates most with you. I encourage you to explore different games and see what speaks to you!