Um, forgive me, but I believe everyone who's suggested something thus far is missing the obvious. That is, they're failing to see the logical solution to the damage portion, at least, but I'll get to that later.
First of all, for the move part, use that trigger that moves a unit instantly to a "point with polar offset" (sorry, I don't have my World Editor on this computer, but I believe that's what it's called). Assumedly, your hero is melee, as this sounds a lot like DotA's "Blink Strike." Thus, you want your unit to be offset from its target by a range of 100 (melee range), and you can either make it select a random number of degrees (by having it use the "random integer" function and setting your bounds at 1 and 360), which will orient your hero at a random location around its target, or you can set the number of degrees to the "angle between two points" function, the first point being the initial position of your unit and the second being the position of its target. This will make it appear 100 distance from its target in the direction from which it originally came. However, if this is the case, you have to store the unit's initial position as a variable, elsewise it will take the angle from the unit's new position (100 distance from the target in God knows what direction). Finally, you should order the unit to face its target, just to make it look more realistic.
(Once again, sorry about not having my World Editor here, elsewise I'd just put up the code, but if you're patient, I can have it up by the end of the week, when I return to my normal computer).
OK So now that you've got the position, on to the damage thing. Several people have suggested area of effect damage triggers. While this is technically doable, it's a pain to work out, it's often buggy, and it can actually damage your own units. Instead, simply use the action that "damages a unit," under the "Units" sections of "Actions". Voila. That makes your life a whole lot easier, as all you have to do is simply set the damage. You can even then add in another action under the "Floating Text" section of "Actions," setting the color to 100% red, 0% green, and 0% blue, then using concatenate strings to display, for the first string, the actual damage dealt (using the "convert integer to string" option and setting the integer as the damage dealt to the target), and, for the second string, simply an exclamation mark. This will make it appear exactly like a critical strike, although you'll have to tweak the fade point and duration of the floating text how you want it, obviously. You would also have to set the duration of the floating text to limited, I think, or else it will stay there forever. I forget the exact action for that, though. Anyway, play around with what I wrote, and I hope it proves helpful, or at least enough to get you started with this ability. Of course, what I outlined above was merely how to do the "DotA Blink Strike TM" (with enhancements :shades: ), but like I said, feel free to tweak it in whatever direction you'd like to take it.
Sincerely,
Hot Soup
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