the daycare
Nope, repel is a shiny's worst enemy >:(
you have to be lucky
You can get Zoroark by trading an Event shiny beast Pokemon to Pokemon Black and White via the Relocator.
There is no possible way at the moment except by using the Event Shiny legendary dogs to get Zoroark and breed it.
The chances are exactly the same as when two non-shiny pokemon breed. If you breed with a Pokemon from another language game (ie a Japanese and a US pokemon) the the chances are increased. In D,P,Pt, HG&SS, it is five times more likely. In Black and White, it is six times more likely.
It doesn't matter in any way if the parents are shiny or not, it has absolutely no effect on the chances of a shiny offspring. When breeding two pokemon from different locations (such as one from Japan and one from the US) the shiny chance increases by six times, in Black and White (5 times in the other DS games). So the chances with the above pairing, whether shiny or not, is 1/1366 of having a shiny offspring.
You can get Zoroark by trading an Event shiny beast Pokemon to Pokemon Black and White via the Relocator.
It increases the chance of finding shiny pokemon. How much is currently unknown.
Minccino
Ditto can breed with anything except legendaries.
No, Victini is unbreedable.
masuda method: which is to trade for an out of country Pokemon you want, and to breed it. (use the global trading station) this will lower the 1 out of 8,029 chance while breeding to a mere 2,400ish.