Humility reads: 'All creatures lose all abilities and have base power and toughness 1/1.' The phrase 'lose all abilities' is comprehensive — it strips keyword abilities, activated abilities, triggered abilities, and static abilities alike. This is governed by CR 604.3, which notes that continuous effects can remove abilities from objects.
Triggered abilities (CR 603.1) are defined as abilities that begin with 'when,' 'whenever,' or 'at.' Since Humility removes all abilities, any triggered ability a creature has — whether printed on the card, granted by another permanent, or otherwise — is removed while Humility is in effect.
There is an important nuance about layer ordering (CR 613): Humility operates in layer 6 (ability-removing effects) and layer 7b (setting base power/toughness). If another effect grants a creature an ability in layer 6 after Humility's timestamp, that granted ability may persist. But abilities that are part of the creature's printed text or granted at an earlier timestamp are removed.
Concrete example: You control a Grave Titan (which has 'Whenever Grave Titan enters the battlefield or attacks, create two 2/2 black Zombie tokens') and your opponent controls Humility. Grave Titan attacks — its triggered ability does not trigger, because Humility has removed it. No Zombie tokens are created.
Note: Humility does not affect triggered abilities on non-creature permanents, only those on creatures while Humility is in play.
Unofficial fan resource — not affiliated with or endorsed by Wizards of the Coast. Answers are AI-generated estimates grounded in the Comprehensive Rules and are not a substitute for an official judge. Verify anything match-critical.