Castle of the Winds

Except for the first dungeon, all of the maps and items are randomized with every play. A good trick for finding decent items is to save your game before you descend into a new level, then use the Detect Objects spell to see what items the game spawned.

There are always hidden doors & paths on a level. Moving around the edges of a room and pressing 's' for search is one way to uncover those (and potential traps), or you can use the clairvoyance spell to unveil blocks of the map.

It is best to avoid fighting Gelatinous Cubes in hand-to-hand combat as they can deals dozens of hits at random, thus ending your quest rather quickly. Use attack spells from a distance if you can. The same goes for Smirking Thieves, as they simply need to get next to you to steal items.

Grabbing the Identify spell early on is useful to avoid placing cursed items on your person, and cheaper/quicker than taking the items into town for identification.

Boots of Levitation will help prevent you from falling into a pit trap that will send you down to the next level.

Slime can only be hurt by fire.