As many of you know nintendo announced at e3 midna will be playable. Later on Famitusu had new information including zant will be making an appearence.

I believe Zant was brought back to life  by Cia and is given a part of her army to take over the Twilight Relm again. Reason being is  this could be another possible explanation of why midna wants to comfront Cia. I think Midna will need Link's help to defeat Zant and bring back order. Then we have the only reason thats confirmed. She wants to comfront Cia for turning her back into her original form. So yeah this is why midna and zant are in the story more than what they gave to us.

Now this theory may be obvious but anyway Cia's magic. It's ganon's that is all i got to say so yeah.

One more thing though this may explain why argorok is back Zant brought him back to life.

Buts thats just my theory got your own?

Isn't Hyrule Warriors Non-Canon? Cause I thought the reason for all the characters being there is just for shitz and just being able to play them... I didn't think it actually has to do with the Hyrule Universe since I think its just a spin-off right?

im actually not really sure if its canon or not i just made it because i thought it was 

I don't think it's canon but I wish it would be. This is essentially turning into a sequel to Twilight Princess except with an actual war.

Aonuma confirmed that Hyrule Warriors is "canon." He did use that word. But he clarified that it takes place I a a sort of alternate universe from the rest of the series, like how Majora's Mask is canon despite most of the characters not actually being the people of Hyrule.

If I had to guess, I bet one or two characters (Ganondorf probably) will be visitors from the main timeline.