Prerolled Perception Checks (Patreon)

This is an alternative to a certain type of passive check.

While the passive Wisdom (Perception) score (aka, passive Perception) definitely has its use, the static number for it, in my opinion, is too predictable and often lacks the ability to fail against anything but higher DCs.

Doing Prerolled Perception Checks adds in that bit of uncertainty, while still keep the timing of the DM's use of those checks hidden from the players (so they're not doing the metagamey "we had to roll Perception, something must be here" routine).