Yeah I don't see how marill is the clone, it's more of a 'copy' and infact like bulbapedia says on all of pikachu, pichu, minun, pluske and pachirishu but NOT marrill's descriptions, they follow a similar structure and look with cheek patches pointy ears and same typing.
Marill is just regarded as a pikablu since it has a zigzag tail and is called the same species, but besides from being a kind of fat blue bouncy mouse it's not close enough to pikachu to be considered a 'clone', atleast in my oppinion and seemingly the people of bulbapedia.
In a sense Marill was drew from a photo of pikachu, the others where drew from pikachu itself.
So yeah I just don't see how Marill can be a 'pikaclone', it's much too different to pikachu especially since it's weak to him.
Also from this I wouldn't class Chiraamii as one either.
Now a matter of being on topic.
Well when it comes to Zorua and Zoroark I guess they really are event only which just plain annoys me, I wanted Zoroark in my team and I thought it could get in my top 10 favourite list but now I'm just put off it.
What happened to legendaries being the special event pokemon? Sigh.