Ash only saw him for like 3 seconds in Mewtwo Returns.
I don't think it was only for 3 seconds. It was more than that.
Also even if he saw him for like your saying 3 second, if the writers had considered the events of
Mewtwo Returns as canon, they should have atleast had Ash act like he had seen him before, though he couldn't remember were or who he is.
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Well aside from that, i really liked Meloetta's reactions in this episode.
When it challenged Oshawott, it was like she is saying to Oshawott to "bring it on" and then seeing his hesitation she was like "come on, fight" and when Oshawott forfeited, her reactions was like "what was that for". And then during her fight with Krookodile it was taunting it to "bring it on" and acting like "is that all you got".
I also like Krookodile's reaction when his
Stone Edge was blocked, it was like "what the, how did that happen". And then when Meloetta was like "bring on more", Krookodile was getting heated up.
I don't know how many times i have said this but i would it again. Why couldn't the writers make Ash catch Meloetta, it is so perfect for him.
But sadly he isn't catching her. Also though i am not sure, but i think it was sort of confirmed in this episode that there is a ban on catching Meloetta or something. I maybe mistaking it though, so can someone confirm it for me. But if it is true, then there is no future possibilities of Ash catching one either.
Why are the writers like that. They can give Darkrai and Latios to a trainer like Tobias without any reason, give a Heatran to a random trainer during the league who can't even qualify to the Top 8, and give a Latias to a Nurse Joy who is a inspector of the PIB. But can't give a moderately powerful legendary like Meloetta to Ash.