Ring of protection
A ±X ring of protection affects the AC of the wearer by X (ranges from -6 to 6). If X is negative, the ring is normally cursed. Even if you've identified rings of protection in general, you won't know the specific amount of protection a given ring offers until after you've put it on.
Depends on the strength of the ring. All characters are going to want more AC, but sacrificing a ring slot for it may or may not be a good idea. A +1 ring is something you'll likely only use until a decent alternative comes around, but a +4-6 ring may be worth wearing through to the end of the game.
|Amulets||Acrobat • Faith • Guardian spirit • Gourmand • Harm • Inaccuracy • Magic regeneration • Rage • Reflection • Regeneration|
|Rings||Attention • Dexterity • Evasion • Fire • Flight • Ice • Intelligence • Magical power • Poison resistance • Positive energy • Protection • Protection from cold • Protection from fire • Protection from magic • Resist corrosion • See invisible • Slaying • Stealth • Strength • Teleportation • Wizardry|