Triggered abilities always begin with ʺWhen,ʺ ʺWhenever,ʺ or ʺAt.ʺ Examples would be Deceiver Exarch and Glint Hawk Idol. If an ability doesn’t begin with any one of these words, it’s not a triggered ability.
Abilities like the ones on Phyrexian Metamorph and Phyrexian Revoker, even though they say ʺenters the battlefield,ʺ aren’t triggered abilities because they don’t start with ʺWhen,ʺ ʺWhenever,ʺ or ʺAt.ʺ Torpor Orb can’t stop these abilities from being used. They apply the moment the creature enters without using the stack, and definitely without ever triggering.
Today’s Rules Tip written by
Jen Wong, Level 1 judge from Irvine, CA