Hey no problem. This is going to be a bit ugly, but hopefully it helps.
SET UP SWITCHES
Create New Event - on map, right click any square while in event mode, select new.
Top left, under conditions, click Switch checkbox
Next to checkbox, click button that opens Switches window
Choose two switches, in this case 0001 and 0002.
Name 0001 Captain's Rage Harmful
Name 0002 Captain's Rage Safe
Click OK on Switches window
Cancel out of Event window (Discard Changes to this Event? YES) you just want to get the switches set up
Both switches are OFF by default
NEXT STEP
TOOLS > DATABASE > TROOPS
For this example we're going to select 0001 Bat*2, which is a troop of 2 bats. The bats enemies are already set up by default. You'll change this according to your needs.
Click Conditions button
Check the Switch checkbox. Switch 0001, Captain's Rage Harmful
Click OK
Back on the Troops page, you will see a box with several lines in it. At the top is a black diamond. Double Click that line
At the top of the Event Commands window there are three tabs, 1, 2, 3. Click tab 3.
Under the label BATTLE you will see Force Action. Click the Force Action button.
We want Bat #1 to attack the Character in Index 1 (in this example. i think the index number corresponds to Actor ID, which is the order they are in in your database. Maybe he's the 3rd actor, so you select Index 3 -- again, i think this is how it works, not 100%. if this is wrong, there are other ways to handle it. but try this first.
Click OK.
You will now see Force Action : #1 Bat, Attack, Index 1
Double Click the next line, which will now also have a black diamond on it.
Repeat the process, this time for Bat#2.
Click Apply button.
NOW WE SET UP COMMON EVENT TO CHECK IF Captain's Rage IS DANGEROUS TO THE USER
Click on Common Events
open slot 0001
Type Captain's Rage Check in the Name box
Double click the line with the black diamond
in the Event Commands window, click on Tab 1
then click the Conditional Branch button
in Tab 1, the Switch radio button will be selected by default. Click the button and change the switch to 0002 Captain's Rage Safe
click the checkbox Create Else Branch
You will now have a condtional branch in your event.
Go down to the line below Else. Double click, under Tab 1 select Control Switches.
Set switch 0001 Captain's Rage Harm to ON.
Click OK
Click apply
NOW WE SET UP THE SKILL
Change maximum number of skills to 11 (or whatever, just larger than 10)
For our case, we're going to use skill slot 0011.
Enter Captain's Rage in Name field. Set up the damage however you want (this can wait)
Double click under Effects
Click on Other tab
Click radio button for Common Event
Select 0001 Captain's Rage Check in dropdown menu
Click OK
Click apply.
This is the basic set up. After the fight, you'll need to turn the switches back off using eventing. If you get stuck at that point, I can help, but you should be able to work your way through it. Just play around. You'll learn as you go.
At the point where the char learns to use the skill safely, set Switch 0002 Captain's Rage Safe to ON. This will mean that the check clears and it will not result in the char being targeted.
Again, this is just the bones of how you could do it. There might be other ways, for example by using script calls. But i think this is the easiest way for a beginner and it will help you understand how things are connected in the database, which is very important for getting the most out of RPG Maker.
