How to isolate the AI from human players:

Steps
1: Place one water hex underground, place one water hex on the surface right above it. Avoid having other water hexes within i+19 (initial hex plus 19 outward) for surface to surface or underground to underground. Avoid having other water hexes within 1 level change i+9 hexes.
2: Place a ship (transport) on the underground water hex near the human players
3: Give each player a wizard tower with Warp Party
4: If you warp party while on the ship, it will go to the only other valid water hex.
Walla! You are able to move parties between the underground and the surface (Undead realm where they are recreating their planar rift to travel back to their realm), but the AI will not be able to.

How to make a good triggered AI attack:

1. Use inverted terrain on the surface
2. Use Altars to 'melt' the inverted terrain
3. Use ruined water mines to protect some inverted terrain from melting.

Put teleporters in the Undead homeland and guard them with black rock. Place death Altars in such a way that when they trigger they melt the black rock. Have the teleporters transport the Undead into human players' territory. Use a trigger to decide when the teleporters open up (example: a human player moves too close, or have another AI player teleport into the blast zone during turn X).

Don't want the black rock to melt? Make a mine (or regular mana node). Set it to ruin. Place a water hex underneath it. Select the mine. Copy the mine. Paste it over the black rock. The ruin will overlap on top of the black rock. This will protect it from the melting effects of terrain changing altars (and it will be permanently impassible).

Blimey. I think I'll probably just use one-way teleporters for the Undead menace - the AI does use them.

The warp party thing is very cool. I think I'd have it so that the only way to win the map - as would be explained to players - would be to build a shipyard, then a boat, then enchant it with fire halo, then cast warp party until it ends up on an otherwise inaccessible lava area in the caverns, which would count as having escaped to another plane of existence (and I could make it look weird by mixing lava with grass/snow/forest tiles or whatever else). So you would be building your escape method with two construction commands and two spells!

if there's a couple bodies of water at which to build a shipyard, then you might need to cast Warp party several times? I don't understand this thing about 19 hexes distance, or 9 hexes + 1 level change: warp party isn't fully random or has a range limit?? Something to experiment on.

Surface cave melting is also extremely cool, maybe it'd be needed to reach the body of water. (can't be used underground because it crashes, right?)

Warp party will take you only to a random hex that your party members can validly spawn onto. A neat trick is using boats to bounce upstream of a river, because an unenchanted boat can only spawn on water. You can test it out to see, it will have a max range of +19 hexes for same level warps. Max +9 hexes for jumps between surface to underground or underground to depths, and can't warp directly between surface and depths.
I'm not sure how it interacts with magic sanctuaries or other structures.

I tried underground altars but didn't experience any crashes on basic terrain (water, dirt, rock). It's possible the stories of crashes are related to changing underground cities

Work on my item set for AoW1 is coming along well. I will include an item or two for each person in my aow emails list, so if you want to specify what the item should be and what powers it should have, do say.

Many item graphics exist that were never used for items, and I am making two items per graphic, so when work is complete there will be three times as many as before. Furthermore, I'm using a mod that enables all abilities for items, so a lot of wacky or unusual stuff can be done. Most of the items will be reasonable but generally stronger than the base game's selection (which is mostly very lame, actually), and I will not include items that grants Physical Immunity or Flying.

So much for my wand that grants Physical Immune, Magic Immune, Flying, and Archery. :(

Actually, I might include Flying, maybe even Physical Immunity, but it'd have to be in conjunction with negative effects like Poisoned, Cursed, and Vertigo (that's the only way to get negative stats on items)

Wand with Flying, Physical Immune, Magic Immune, Poisoned, Cursed, Vertigo. I can find other immunities on other items or spells and be untouchable.

No way am I putting Flying and Physical immune on the same item, nor Physical and Magical Immune :p
Care to pick which you prefer? I reckon Magic Immune, Flying, Vertigo, Cursed, Poisoned would be... interesting.

Honestly, I think Flying + Magic Immune is already too powerful. Poison, Curse, and Vertigo don't really matter when archer stacks are your main threat anyway.

What really made me jealous was Jyri's named ring, with Vision 4, True Sight, and Invisibility. I'd take one of those in a heartbeat, and even faster if you added Night Vision to it (dumping True Sight to give it Night Vision would be more than acceptable).

Being Poisoned, Cursed, and Vertigo-ed all at once would reduce your DEF by 5!

Irrelevant if they can't attack you in the first place. I did note that archers would be a problem, but they're going to be what hunts your flying hero anyway. Magic immune cuts off the second most common ranged attack (and most priests), and various items and spells can provide other immunities. Or simply fly away from a given threat. Flight is amazing.

Also, defense boosts can come from levels and other items. You just need a few more to offset the inherent problems. You could also possibly remove the item for a battle, like to wipe a small stack of archers.
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Can you add "Burning" to an item? That might make for an interesting drawback.

Whenever I tested it, burning and decay showed the animations but didn't apply damage

Don't forget fury and fear!

While the defense drop looks kind of bad, I've found the fury spell is indeed a buff to units that use Strike (archers don't get the benefits).

Fear would be crippling, since a unit that is Feared only runs away.

I'll use this post, and edits, to track wins and losses versus Mimo now that he's returned. I always wondered how bad my winrate against him was.

PBEM name, victor, turn listed below

Generated 1v1 - Mimo, turn 23
Danny's Sock - in progress