1) The coloured dragons, the Great Wyrm, and the Supreme Titan are level 6 monsters who give treasure every time, and it is only from them that you can rely on getting the the top-class loot. You can get level 6 (L6) treasure from other monsters, but it's usually limited in either type, frequency, or both — for example, the Maddening Eye can give you L6 treasure, but it only hands out rings, and it only has the chance to do so 30% of the time, so that even when it does give a ring, there's no certainty it will be an L6. The Cuisinart behaves similarly with its plate armour. The top class genie, the Efreet can give you an L6 treasure 30% of the time, but in my experience seldom does. And that's pretty well it.2) In my experience, the treasure you get from a monster is absolutely random within a) the pre-set limits for that monster and b) the ability of the game's subroutines to produce absolutely random numbers. Over the years I've been playing this game and reading about other players' experiences, I've seen all sorts of theories, especially about the "Enchant Item" spell. You know: "You get best results 'in a morning' or 'on one-day' or 'during the last week of the month'" and so on. None of them have held up when they were statistically analysed using a large enough sample to make the analysis reasonably valid.
There were all sorts of stories about the game, hidden dungeons wonderful weapons, and all that. They don't exist — trust me! Reading through the games files with a hex editor, I did find one weapon that I'd never seen in the game (I can't remember now what it was other than it was a sword of some sort), but when I resurrected it, it was a huge disappointment when it turned out to be only a +2 weapon. Apparently it had been used in developing the game, and the data on it had not been removed from the resource files when the game was finally marketed.
