Help! My strategy in the two most recent games was to summon Malleus the Magician and make him invisible, then send him everywhere solo. So I made him an item the game called Amulet of Invisibility, with Invis and + attact and + to hit. Then when he equipped it, his icon became grayed out. So far so good. But when he went into a lair, he was not invisible. The spiders saw him and webbed him, and then the other thing flew at him and ate him. I restarted a new game and the same thing happened. Does anyone know why?

Possible reasons:

1) Known bug? Quote from http://www.gamefaqs.com/pc/564960-master-of-magic/faqs/2059 :
Invisibility items don't make you invisible in combat.
(I'm not 100% sure about this as I have never enchanted invisibility items before...)

2) Known bug #2. Enemies always know where you are at the start of the combat. You need to move at least 1 square away before they lose track of your location. I've encountered this numerous times when using Nightblades & Shinbo (naturally invisible units). The enemy will charge towards me & engage in melee if I do not move my invisible units.

If that's the case, then your Malleus must have been continuously webbed by the spiders until the gorgons(unknown flying monsters) got close enough to melee him. I'll suggest sending in a few "junk" units in with Malleus to get the spiders to waste their web spells.

3) Highly unlikely, but maybe the unknown flying thingies you described is able to sense invisible? Either true sight (Angels) or immunity to illusions (Demons)? Off hand, I don't recall ever seeing a lair that contained monsters from 2 different spellbooks or a flying nature monster that is able to sense invis, but I could be wrong....

Hope it helps. :-)

I think it must be #1. That's a drag bcuz I can't do anything about it except give Malleus invis from the spell instead of an item. That would mean being at risk of it being dispelled, which could get him killed. :(
Thank you very much!

Items only work on the world map and all dead can see invis anyway.
There is also a Life spell that gives you see invis.