[help me + request] item & spell

dunno which place i should post this. if i'm wrong just move.
Before and after i only know about triggers, i'm blind at jass T_T

the first thing is i need to know how to make such as item restriction to a hero.
I mean heroes cannot have same 5 items in his slot. how do i apply the restriction?

the second thing is a request, can this spell be made? if this spell can be made would somebody made it for me?
The base idea of this spell is like the chariot. The horse eventually drag the chariot right. I want to make a spell that using arthas or any mounted unit that can target a unit to be dragged, the targeted unit is move following (dragged) wherever the mounted unit go.

So it just like achiles drag hector when he won the fight.
Or western sheriff drag the bad guy with their horse

There are a few ways to do the item thingy... it all depend on if you want to use item-type, item life, item level, or custom value.... then you can just set up your trigger like this:


and where the "If - Conditions" is would be where you would put one of these 4 conditions depending on what you wanted to use....

This is an really easy way to do it.

Ah thank you very much, it really worked, but
what if i want the hero can only carry 2 of the same item,
how should the trigger be?

Umm. and ismy idea of spell can be made?

Ofcourse it can be made, just not maybe exactly as you imagine it.
though it's a bit complicated and I dont have the time to do it for you right now.