How Strong Are Ash's Newest Pokémon Compared To His Older Ones?

Ash has been relying primarily on his newest Pokémon to battle the world

Ash Ketchum and Pikachu are leaving Pokémon. What's next for the series? - Vox

10 Times Ash Ketchum Showed He's a Very Mature 10-Year-Old

The Evolution of Ash Ketchum's Teams Through Eight Generations of Pokémon

Why do the partners of Ash from Pokemon keep changing? - Quora

Would you rather remove Ash or make him grow older? : r/pokemon

Pokémon: To Be a Pokémon Master (Anime) - TV Tropes

Ash, Pokemon X and Y anime Wiki

Ash and Pikachu retire in 2023, Pokémon to introduce two new main characters

Ash's Old Pokemon Are TOO WEAK for MASTERS 8?

Pokémon: 10 Times Ash Acted His Age (& Suffered For It)

Pokémon: Ash's Best Pokémon From Each Region