HOW DO YOU GUYS SET UP BOSS BATTLE AI?

The 'Elements in Boss Battles' thread got me thinking about boss battles a bit. I'm now wondering, what have you guys set up for boss battle AI?

I'll give you an example of what I mean, taken from my entry in a 2k3 'boss battle' one-week challenge I took part in once. My battle was three phases long - 1st phase, four weak throwaway enemies. Second phase, a pair of stronger enemies. Third phase, the actual boss.

The single PC had a full set of six usable actions - attack, hammer(stat-breaking), tool(elemental damage), First Aid(healing), 'Winter' (a set of miscellaneous moves involving the dog traveling with him), and item.

In the first phase, the enemies had no AI whatsoever; they were simply there for the hero to fight. Attack, defend, one special move - all at the same priority.

The two second-phase enemies had been designed to work with each other; they were intended to heal each other when weak, and getting rid of one meant the other would start throwing more powerful attacks.

It was the third phase, however, where I was trying to allow the AI to shine. The idea was that the actual boss, in addition to trying to tire you out with his minions, had been watching you the whole time, paying attention to what you were doing. He had three basic actions - attack, a lightly-damaging magic attack, and a light healing ability - he could use no matter what. The rest of his bag of tricks depended on how you'd fought his underlings.

Spammed attack against them? Then the boss would use his own anti-attack abilities; you'd take damage while trying to reach him from spikes he scattered on the floor, he'd attempt to pummel you while you were swinging at him, and he'd start using his major healing ability.

Kept attempting to break the enemies' stats with the hammer skills? He'd spam his own stat-raising skills before trying to attack you, and bring them back up again if you did succeed in lowering them.

Tried to use your tools to fry/shock/blast the enemy into oblivion? The boss would raise his defenses against them - and could do so enough that he could end up absorbing the attacks.

Leaned on the First Aid command? The boss would start from the beginning with his most powerful special and magical attacks, hoping to overwhelm you before you could really get started.

Kept pulling out items to replenish yourself? The boss would attempt to knock some of them away from you; the more often you used them, the more likely this was to trigger. (It was in the 'movement pattern' for him four times, each with its own trigger condition set in the battle event page that tallied this.)

The 'Winter' option was the wildcard; with the exception of one skill, using this ability simply added to the likelihood of one of the other options at random. That one skill, however, was a counterattack ability of your own - and if you kept that up long term, or used it often, then the boss would swap out any of his abilities that could trigger the counter, from any attack pattern, for less-powerful actions that would not trigger it.

The catch to all of this, and what was supposed to be the secret to the battle, was this: Once the actual boss showed up, his plans were set in stone. At least in theory, swapping out your previous attack pattern and using another one would allow you to take him on without too much difficulty.

It was a great idea, but the time limit meant I ended up putting it together in a slipshod manner, and balancing was almost nonexistent. I came in last in the contest, and even I can see I deserved it.

Yes, I recognize using one of my own setups probably qualifies as bragging, and I apologize if it is seen that way. I simply can't think of any RM* projects other than my own where I've figured out the mechanics well enough to describe the AI patterns.

So, as the topic asked: Do any of you do anything like that for your games, and if so, what were some of your best or favorite examples?