Top Ten Pieces of Mandatory Dungeoneering Equipment
10. A map of the dungeon. Not always available, and not always cheap, but always worth looking around for. If there isn't one, consider making one and selling it later...you know there will be a demand for it.
9. Healing Potions. Before you walk into that cave, make sure you will be able to walk back out of it. Buy as many potions of cure moderate wounds as you can afford. You can never have too many.
8. Pouch. You can't really carry everything around in your hands, and a backpack can be hard to get to in a hurry. Store all of your little bits and pieces, and a healing potion or two, in your hip pouch.
7. Ten-Foot Pole. Sure it's cliche. It's tedious. It's silly. But thanks to the thirty-seven quadrillion different ways to boobytrap a chest in this game, it is extremely necessary. Use it to poke things, sure, but also to vault across pits, to stir a cauldron, or to pilot a raft. Snap it in half and use it as a quarterstaff...or snap it to bits and use it as firewood.
6. Waterskin. You know how it is. Sometimes you get thirsty. Sometimes you need to wash poison off of a doorknob or treasure chest (or your hands). Sometimes you need to douse a campfire (or companion). That is where this inexpensive, albeit heavy, item comes in handy.
5. Bottle of wine (or mead, or brandy, or whisky). Obviously, alcohol is a delicious and valuable beverage that no adventurer should be caught in short supply of. But in addition to calming one's nerves and quenching thirst, it can be used to bribe or seduce NPCs, or to create a rudementary firebomb. And according to the red-box rules, some poisons are sticky and can only be rinsed off with alcohol.
4. Rations. In addition to providing a meal, those rations can be used to bribe less-intelligent monsters, or to bait/distract beasts and animals.
3. A piece of chalk. Use this inexpensive, nearly-weightless item to track your progress through the dungeon, to mark your way out, or leave messages and warnings (or taunts and insults) to those who might be following you.
2. Torches. You need a light source, and an open flame can help you detect things like drafts and bad air. Sure, you could use a lantern, but torches just look cooler...and in combat, they can be used as clubs. Flaming clubs, even.
1. 50' of Rope. From helping you scale the cliffs or bind the monsters that guard your quarry, to helping you lash it down to the backs of your pack mules, this is the one piece of gear that you can't leave at home.