The Pokemon anime has been around for a long time. As such, it's worth considering which seasons are the best of the bunch.

In the US, Netflix has season 1 and seasons 23-25 (The Beginning ... The Pokemon Mega Evolution Specials (Pokemon XY) [4 episodes] The Legend of X, Y, and Z (After Pokemon XY) On top of those ...

Special episodes like the Mega Evolution Specials, essential to the Pokémon XY storyline, had previously been so difficult to find but are now up-loadable into the channel and thus more accessible.