Mirror Image Question

[tieren]

Lets say the caster is on a horse, just a regular horse not a find steed or animal companion or anything, and the caster then casts the spell Mirror Image.

1. What does that look like?
2. Is it any harder to hit the horse?

I am having trouble visualizing the effect. the most natural of course would be to have multiple horses and riders so the enemy doesn't know which is which. However, without some other ability or effect (find steed, twin spell, whatever) the horse is not a target of the spell, and only the rider gets duplicates.

Does that mean one image is on the horse and the others are floating around it? Do they walk along side the horse to appear more real and possibly better confuse would be attackers? Are they constantly mounting and unmounting the horse so I can't be tracked (does that mean I have to walk half the time)?

Regardless of what it looks like there are presumably several copies of me on and around my horse. Even with no copies of the horse in effect is it harder to target the horse? Do all the images create the effect of partial concealment?

[Alerad]

1. It looks like four people riding one horse. Should be pretty crammed.
2. Unless the horse shares your spells it is not harder to hit the horse.

Even when not on a horse the three images occupy your own space, so they are still pretty close to each other. Even when you stay still during your turn the mirror image is active, so they don't need to change. Maybe every time you are hit you and the images shimmer momentarily and changes places.