Need Help im MapMaker -> Europe !

Need Help im MapMaker -> Europe !

If anyone ever played Europe map, he knows whats happening when u r attacking castle and take it life to 25% - u take control of it !! How to make a trigger for that ?? I cant imagine any And i need to know it for my new map

Plz help

unit's health becomes lower than 25% , actions...

Two ways

Untitled Trigger 006
Events
Unit - A unit Is attacked
Conditions
(Unit-type of (Attacked unit)) Equal to Castle
(Life of (Attacked unit)) Less than [value, not something like 25%]
Actions
Unit - Change ownership of (Attacked unit) to (Owner of (Attacking unit)) and Change color

Probably runs too often, but easier

2. way

Untitled Trigger 007
Events
Unit - Castle's life becomes Less than [specific value, not something like 25%]
Conditions
Actions

With this one I'm not quite sure how to refer to the attacker

to 2.
in my opinion, only "triggering unit" refers to it, so i see no possibility to use the 2. way

Very Big THX DarkShadow. I tried many triggers of my own, but never thought about unit-type = castle

IT WORKS !!

Yeah, I know that, sometimes the solution is very simple, but you can hardly find it. Don't ask me how often I created a way around and then saw that I could do it much easier