To get Pupu card (level 5) you must encounter all 4 spaceships ( you must have Diablos ability Enc None to see them) go to the hole where Balamb Garden used to be, and you will encounter another spaceship.
Fight and defeat the spaceship. then you will encounter a Pupu.
You must feed it five Elixers and you will be rewarded by It's card.
It may only be Lvl 5, but it is certainly the hardest to get.
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