Skill That Targets a Random Unit?

Hey guys, hopefully this is a simple one.

I was pondering a new character to add to one of my projects who is a kind of 'clutsy mage' but it solely depends on whether I can simply accomplish a targeting idea. The concept is that her spells will have high damage and critical potential, however limited functionality as they may miss and could also randomly hit an ally, including the caster.

I've searched all over the place but I can't seem to find a script that lets you add that kind of thing and I can't believe that it doesn't already exist :S I figured this would be something common in many projects.

An example of the kind of thing I'm wanting is, say, a Lightning Bolt skill that targets a single random unit (enemy or ally) in battle. Alternatively, the player could choose a target for the skill but have a small chance that the target will randomly change to another enemy or ally upon use.

I'm already using Yanfly's Target Manager (which doesn't allow for this kind of thing by default) if that helps with potential compatability issues.

There is such a script, but it is rather unknown.
SES target manager

Sorry, I don't have the link on my current computers (despite the fact that it was my idea that creates that script), it's on their site.

I took a quick look at it but there were only a handful of instructions for a few examples and none that seemed to show how to set up a skill like the one I wanted. It seems to require a 'core' too which I was a little hesitant to get in case it messed with some of my other scripts.

Unless their 'core' script is badly written, it should not break any games. The idea of core script is a collection of function for scripter's convenient sake, and it should not touch anything regarding the compatibility with other scripts. If this said core is modifying the default engine works, it's a bad core script. I'd say, just try it.

I got it and tried to figure out how to setup a skill but the script doesn't really come with many examples/instructions that give you an idea of how to make certain things.

For example one of the filters is "enemy_only" which makes sense and I imagine "allies_only" would also work but I have no idea what I'd type to make it target either at random.

The default is every battler from both sides, the filters are only to exclude something from the target list.
I don't remember what the command for random scope was, can you link to it?
As said I've only limited computer access at the moment...

Please give a link to the website where the script can be found so that people who want to help can check it.
[move]RGSSx Script Support[/move]

Ah I'm sorry :/ I'm terrible at knowing what my questions come under in terms of category.

This is the site: https://sesvxace.wordpress.com/2014/08/04/target-manager-v1-0/

And this is the direct script: https://raw.githubusercontent.com/sesvxace/target-manager/master/lib/target-manager.rb

OK, here is the short version:

By default, everything (both actors and enemies) are in the target group.
The filter is the part where you remove targets from the list - for example with the filter for enemy only youi remove all actors from the target list.
The part behind the "Target manager" in the opening line tells how many or which targets from the list are really selected for the skill.

<Target Manager: rand 1>
</Target Manager>
Would result in a skill that hits one random target of everything, either actor or enemy.

As said the filters are only needed if you want to exclude possible targets, for example if you want the skill only to target wounded battlers or only actors or whatever.

That's awesome and much simpler than I imagined but unfortunately I just discovered that in-game the SES Target Manager brings up a 'target select' message box which seems to have replaced the one that came with MOG's Battle HUD and the new one is positioned BEHIND my characters so I can't even see it :/ so it's probably not something I can use after all unless I can disable that particular feature?

You can try placing mogs script below the target manager, but unfortunately yes - such a rework of the target system does require a rework of the target selection window.
So you would most probably require a patch to make those scripts compatible.