I recall there being a guide for adding and learning 'Blue Magic' aka 'Enemy Skills' to RPG Maker however I can't seem to find it, so I've decided to post a 'How To' guide for the method I use in my game commonly known as the 'Monkey See Monkey Do' method.
What is the 'Monkey See Monkey Do' method? This method is when the monster uses the skill in battle with your Blue Mage present and learns the skill regardless of who the skill was used on.
Step 1First you must make your skill and tailor it to your purpose. Applying your game's 'Blue Magic' skill group if needed.
Step 2Make the monster that will use the skill you made and set the skill to turn on a switch, it is preferable to us a switch specifically for use in battle that you will turn on and off multiple times. (I have 10 'Battle' switches for this and other battle purposes.)
Alternatively you can create separate switches for each Blue Magic in your game. This is advisable if you intend to have several Blue Magics in a single monster group.
Step 3Create a Common Event and name it 'Blue Magic Learning' or your choice. This will be the primary event used for learning all blue magics.
Step 4Create a Conditional Branch with the Condition of the character who will be learning the blue magic being in the party. If you have more then one character who can learn blue magic create a second, separate branch for that person.
You can also create a second condition within the same branch with the condition that the character not be afflicted with your game's 'Death' condition. This is optional.
Step 5Inside the Conditional Branch(s) create a switch and name it 'Blue Magic Learning' or if you have multiple Blue Mages name it 'Name Blue Magic'. Have it turn on if the party member is present and turn off if they are not or are dead. Your script should look something like this:
Single Blue MageCODE
<>Branch if Blue Mage in the Party
<>Branch if Blue Mage Death Condition.
<>Switch Operation:[####: Blue Magic Learning]OFF
:Else Handler
<>Switch Operation:[####: Blue Magic Learning]ON
:End
:Else Handler
<>Switch Operation:####: Blue Magic Learning] OFF
:End
Multiple Blue MagesCODE
<>Branch if Blue Mage A in the Party
<>Branch if Blue Mage A Death Condition.
<>Switch Operation:[####: Blue Mage A's Learning]OFF
:Else Handler
<>Switch Operation:[####: Blue Mage A's Learning]ON
:End
:Else Handler
<>Switch Operation:[####: Blue Mage A's Learning] OFF
:End[
<>Branch if Blue Mage B in the Party
<>Branch if Blue Mage B Death Condition.
<>Switch Operation:[####: Blue Mage B's Learning]OFF
:Else Handler
<>Switch Operation:[####: Blue Mage B's Learning]ON
:End
:Else Handler
<>Switch Operation:[####: Blue Mage B's Learning] OFF
:End
<>Branch if Blue Mage C in the Party
<>Branch if Blue Mage C Death Condition.
<>Switch Operation:[####: Blue Mage C's Learning]OFF
:Else Handler
<>Switch Operation:[####: Blue Mage C's Learning]ON
:End
:Else Handler
<>Switch Operation:[####: Blue Mage C's Learning] OFF
:End
Step 6Create the monster group(s) for the monster you previously created that uses your Blue Magic and in the Battle Events set the condition for the switch the monster will turn on when it uses its blue magic skill.
Step 7Have the Battle Event Call your Blue Magic Learning Event. Then create a Conditional Branch for your Blue Magic Learning Switch being ON.
Step 8Create a second Conditional Branch within the first, create a switch named after the skill (ex 'White Wind Learned') and set the condition for the switch being OFF.
Step 9Create a message with your Blue Mage's name saying they learned the desired skill and add the skill to their skill list. You must then turn the associated switch on so the event will not be executed again.
For multiple blue mages you must copy and paste both branches and create separate 'Skill Learned' switches for each mage.
Step 10Turn off your 'Battle' switch or whichever switch was turned on when the monster uses their Blue Magic skill. Your script should look something like this:
Single Blue MageCODE
<>Call Common Event: Blue Magic Learning
<>Branch if Switch [####: Blue Magic Learning] is ON
<>Branch if Switch [####: Skill Learned] is OFF
<>Message: Blue Mage learned Skill!
<>Change Skills: Blue Mage Skill Add
<>Switch Operations: [####: Skill Learned] ON
:End
:End
<>Switch Operations: [####: Battle] OFF
Multiple Blue MagesCODE
<>Call Common Event: Blue Magic Learning
<>Branch if Switch [####: Blue Mage A's Learning] is ON
<>Branch if Switch [####: Blue Mage A Skill Learned] is OFF
<>Message: Blue Mage learned Skill!
<>Change Skills: Blue Mage Skill Add
<>Switch Operations: [####: Blue Mage A Skill Learned] ON
:End
:End
<>Branch if Switch [####: Blue Mage B's Learning] is ON
<>Branch if Switch [####: Blue Mage B Skill Learned] is OFF
<>Message: Blue Mage learned Skill!
<>Change Skills: Blue Mage Skill Add
<>Switch Operations: [####: Blue Mage B Skill Learned] ON
:End
:End
<>Branch if Switch [####: Blue Mage C's Learning] is ON
<>Branch if Switch [####: Blue Mage C Skill Learned] is OFF
<>Message: Blue Mage learned Skill!
<>Change Skills: Blue Mage Skill Add
<>Switch Operations: [####: Blue Mage C Skill Learned] ON
:End
:End
<>Switch Operations: [####: Battle] OFF
This Battle Event must be made for any monster group that contains your learnable Blue Magic skills.
Note: If your monster group contains more then one Blue Magic skill the skills must turn on different switches for the event to work properly. Separate pages must then be made for each switch turned on.