Base creature values. Events, world settings, difficulty and loot bonuses can change an encounter.

a monk
Can hasten itself with a defensive ability.
Creature resistance values; world limits may adjust them. Negative values indicate a weakness.
Invisibility
Base chance per roll, not a guaranteed reward. Bonuses, world multipliers and boss participation change the result. Charged items use their own quantities. Container contents also require the container to drop.
bread · 1 · 20%
gold coin · 1–18 · 15%
book of prayers · 1 · 4.93%
rope belt · 1 · 2.95%
ankh · 1 · 2.24%
scroll · 1 · 2%
life crystal · 1 · 1.002%
safety pin · 1 · 1.001%
daramian axe · 1 · 1%
lamp · 1 · 0.88%
brown flask · 1 · 0.82%
sandals · 1 · 0.71%
staff · 1 · 0.44%
power ring · 1 · 0.1%