What's wrong with my Zoroark?

Question

So, I was playing my X game today, and I went to check on my two Zoroark in the Day-Care Center. They had been there for four months now, as I was trying to get a shiny Zorua, so I could get a shiny Zoroark. I got the most recent egg, and started biking to hatch it. It finally hatched, and it was shiny! I was so happy that I could finally get a shiny Zoroark. So I just kept battling The Elite Four with my EXP Share on, and It evolved! I saved my game and then kept on using the EXP Share, and It took forever, but I got it to Level 60. So then, I actually sent out Zoroark to battle The Elite Four, but Illusion didn't work! I hadn't tried Zorua or Zoroark, and so I didn't know this until then. I was so disappointed, to have a Shiny Zoroark that didn't do what I wanted it to do. I don't know why it didn't change, and its ability is Illusion, so whats going on?

By the way, would just going to the Pokemon Village and hunting for a shiny Zoroark, be easier than just breeding and hoping that an egg will hatch into a shiny Zorua?

Comments

I don't even know how I managed to get lucky enough to get a shiny Zorua through breeding. Even though it did take four months, how am I lucky enough?

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When a Pokémon with the Illusion ability switches into battle, it takes the form of the Pokémon in last place (6th) of the player's party. Illusion will not activate if the Pokémon in last place is the same species or is fainted.

Is the last Pokemon in your party faint?

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Or perhaps one of your other Zoroark?

Answer 1

If your Zorua/Zoroark is in the last slot of your party, Illusion will not work, nor will it work if the 6th Pokemon is fainted. This is the only possible explanation as to why your Illusion failed. Also would like to add that even if Zorua/Zoroark is in the last slot, Illusion should still activate in Generation 6 (granted they are the same species). Even if you switch out after losing Illusion, it should reactivate upon switch in even after taking direct damage.

Source. I also tested this all out on Pokemon Showdown myself.

Answer 2

Method 1 is that all of your fellow Pokemon fainted.

Method 2 is as bit more obvious, and that is that you had the Zorro that you switched in in the last slot before the switch.