Wally gave me another idea for a Nethack clinic. Armor.
Getting a low AC is a very important thing in Nethack, it will lower the chances of an attacker hitting you, as well lowering the amount of damage you sustain. Also certain armor will help you in other ways.
Big first thing to do is note that Nethack is a hard-hat area! Falling Rock Traps can be generated on just about every level of the game, and for a band new character, or one that’s wounded it can be fatal (it can also kill your pets), also piercers surprise attacks work the same way. Getting a metal helmet will make you life MUCH easier and longer by reducing the damage done by these attacks. Also later in the game helmets can block the brain-sucking attack by Mind Flayers (you can further improve these odds by greasing your helmet, but the best bet when encountering a ‘Flayer, is to kill it at range, or VERY quickly toe-to-toe.
Another way to save your ass from the start is when you find a pile of rocks stand beside it and search a few times to see if you can discover a falling-rock trap that has been triggered by passing monsters.
So the first hard helmet you’ll likely find is the Orcish helm which is often worn by goblins, but the next likely set of armor you’ll likely find is once you make it to the Gnomish Mines which is the armor worn by Dwarfs that’s Dwarvish Iron Helm, Iron Shoes, and Dwarvish Cloak, and the coveted Dwarvish Mithril Coat. All of these items are metal, so they will interfere with spell casting, but all of these very basic items worn will give you an AC of 0 without any enchantments or further means. If you find duplicates of armor worn, first determine that it is not cursed by using an Altar or setting it down and watching your pet walk over it (pets will avoid cursed items, and if they step on them they will move “reluctantly”…seeing a pet step on an item without a message is a sign it is safe to wear, if they pick up the item its a sure thing!) and try it on. Its worth it looking through a pile of items for the one unit with a +1 or better enchantment. Also note that Dwarvish Cloaks while providing no Armor protection they are VERY light and sell for a decent amount, so collect all you see and sell them at the first shop that will buy them for big money.
Beware body armor new travelers! Lots of body armors are HEAVY, for non-magical armors (like the Dragon Scales) I Really only like the Leather Armor, Studded Leather, Chain Mail and Scale Mail only if you are desperate, as they weigh you down a LOT. Better to stick with lighter fair until you find a Mithril Coat.
After the Dwarvish armor there are a few other mundane equipment that can protect you, such as leather gloves which will not only give you another cheap AC point, but allow you to pick up, and feel Cockatrice corpses without being instantly turned to stone. Also High boots are identical to Iron Shoes in every way but weigh less, and don’t interfere with spell-casting.
Now of course there’s the magic stuff. Besides the above mentioned Dragon Scale Mail, here are a few items you should keep an eye out for.
Magic Cloaks of any kind, they grant cool abilities like invisibility, displacement, poison resistance, spell-casting bonuses, or Magic Resistance, among others. The Cloak of Magic Resistance is VERY useful as it negates a LOT of nasty effects, but anything you can find is better than the Dwarvish Cloaks as a rule.
Magic Boots, the most useful are the speed boots, as the added speed will allow you to run from most attackers, but also clear dungeon levels in less time, and therefore need less food. As a general rule you’ll want a pair of speed boots as soon as you can get them, but a pair of Water Walking Boots, or boots of levitation can be handy when those effects are needed. I really like to stash a pair of Water Walking boots either in my bag of holding, or someplace I can easily get to, because while they’re mostly worthless most of the time, they are VERY nice for crossing water, and while walking on water you can #dip items unlimetedly. Ideal for blanking potions or scrolls.
There are of course other means to get your AC even lower, but we’ll save that for another day!