Dungeoneers, who delve below the earth, regularly encounter magic, spirits, the dead, and unnatural creatures, would likely frequent amulet markets and might have one upon their first delve, not to mention what they might find clutched in the hand of a skeletal cadaver or an unlucky colleague/rival. Here's a 5ish D20 table to help determine what kind of Amulet they might carry.
Form
1.Tattoo
2. Metal charm depicting (Image)
3. Carved wooden (Image)
4. Embroidered (image)
5. A bell
6. A stone or gem
7. (image) written on paper
8. Preserved body part or bone
9. A living animal
10. A pouch
11. A small humanoid figure
12. A knife
13. A music box containing a hymn
14. Strange-smelling perfume
15. a leaf or flower
16. A mask
17. A ring
18. A seashell
19. a piece of clothing
20. A pendant depicting (image)
Image (roll twice and combine)
1. image of a relevant God/spirit/saint/bodhisattva (likely in a wrathful form)
2. A written prayer
3. Strange unreadable sigils/runes
4. Image of the use/affliction
5. An eye
6. A tally of how many times it has worked
7. An auspicious color
8. An intricate mandala
9. A demon being slain
10. Just the use written in a different language
11. a hand
12. Phallic or yonic symbol
13. A weapon
14. A simple abstract symbol
15. An auspicious animal
16. an astrological chart
17. A serene face
18. A sacred flower
19. Depictions of previous owners
20. a hint of the stipulation
Use
1. Viral Disease
2. Falling
3. Beasts of the woods
4. Mind control
5. Demons
6. Blades
7. Pointy tips
8. Fire
9. Wind
10. Water
11. Rocks
12. Poison
13. Vermin
14. Cold
15. Curses
16. Bandits
17. The Law
18. The Sea
19. Injury of a specific limb (roll on death and dismemberment table)
20. Bad luck
Stipulation
1. Only works once
2. Must be hidden to function (loses its potency if seen)
3. Must be hidden to function (simply doesn't work while visible)
4. Only works for males
5. Only works for females
6. Only works for those who are neither male nor female
7. Ceases to function if the owner makes physical contact with either the opposite or same sex (flip)
8. Ceases to function if the owner carries any other magic items
9. Ceases to function if the owner kills or eats a certain type of animal (mammal, reptile, bird, etc.)
10. Ceases to function if the owner consumes alcohol, potions, and drugs (including tea or coffee)
11. ceases to function if the owner does not spend an hour praying per day
12. Owner must ritualistically sacrifice 1hp of fresh blood per day
13. Only works at night
14. Must be visible
15. Must be held in both hands to function
16. Ceases to function if owner talks about it
17. Requires a simple chant to work (does not function is speech is impaired)
18. Is cursed for another use (roll additional use)
19. Ceases to function if ever taken off.
20. Becomes cursed if triggered by a previous stipulation is violated
Function
1. Gives a sometimes helpful nightly vision regarding use
2-3. Owner adds a Karma bonus to all rolls involving use
4. Owner gets advantage on all rolls involving use
5. Owner removes all penalties involving use
6-7. Fully placebo but gives a Will bonus to all things involving use
8. Owner can destroy/consume it for full immunity to use for a minute
9-10. Owner gets a flat +1 bonus to all rolls regarding use but must call it out
11. Reduces the die size of any damage from use
12. You get a headache every time the use would be about to take you by surprise
13. Complete immunity once (Referee's choice)
14. Complete immunity once (player's choice)
15. Halved damage from the use
16. Absorbs damage from use until destroyed
17. Owner can't die from use (can still be damaged)
18. Owner is granted one extra turn in an encounter fully involving use but it can only be used to run away
19. Once per session, reroll against use
20. complete immunity