How to make units casts abilities?

[ManyFaces1999]

To be specific, I am making a survival map for those who don't know :3 Now I've got a boss unit and it's really cool (for me 'cause it's my first map XD). I've given him A LOT of abilities that make him even harder to kill (not meant for single-player gaming). The problem is, when I tested it, the boss doesn't cast abilities when only 1 player is attacking it :\ he only uses the physical attacks. But, when 2 or more players are attacking him, he uses abilities. But he only uses like 1-3 abilities and I've made a ton of them.

Also, when multiple units are attacking the boss, he doesn't seem to attack. Like, he plans to attack a unit, then changes to another one and it keeps on repeating. Help please? Thank you

 

[Solu9]

You use standard Warcraft 3 abilities. They are hardcoded to be cast if certain criterias are met. Fx. Warstomp will only be cast if 3 or more enemies are in range.

If you want the boss to use those abilities you must trigger him to do so.

Edit:
For the standard attack of the boss, or the lacking thereof when multiple units attack him I can't come up with a answer to.

 

[aple]

You can make triggers to force the boss to use certain spells under certain circumstances.

Like, you do:

Pick every unit in 400 range of BOSS_UNIT
If
Number of Units in (Last Created Unit Group) equal to or greater then 1
Then
Order BOSS_UNIT to (Spell)

 

[Karzama]

You'd have to trigger the spells to be cast single player as most of them use group conditions like said above with War Stomp, some spells like Hex and Cripple generally don't get cast on Heroes either.

The only thing I can think of for the standard attacks is if you have a "If unit is attacked" function on the boss and that is being abused. Otherwise maybe try taking down his acquisition range as he might just be trying to hit the weakest targets.