Pass the Fear structures its challenge system around five difficulty tiers, each affecting not just enemy damage but also the types of rewards, battle complications, and enemy composition throughout a run. The Journey tier provides damage reduction but penalises resource gains, Common offers no modifications, and Hard through Reality tiers progressively increase item rarity odds whilst stacking increasingly severe obstacles like pre-revealed chaos battle scars and enemies from future chapters appearing early.

The progression system gates access to higher difficulties, requiring players to clear at least two bosses before unlocking the next tier above Journey. This design ties difficulty selection directly to hunter choice and player skill, as each tier layer compounds the challenge through different mechanics rather than simple stat inflation, creating distinct strategic considerations for each run.