Challenge Rifts

Challenge Rifts are optional areas that can be accessed via interacting with a special symbol that can appear randomly in the floor. They will always begin with a chest which contains the Blueprints for, one scroll of power and an amulet, as well as many cells. However, once the chest is opened, the exit closes and the beheaded must complete a set of trap-filled platforming challenges to escape.

Fully completing a challenge rift unlocks the achievement "See, that wasn't so hard now, was it?"

Stage

 * Has a 20% chance to spawn in all non-boss biomes and are recognized by a rune appearing at the player's feet similar to those found on the walls which house food and gold for the player.
 * Upon entering a challenge rift for the first time, the Beheaded is confronted by a ghost that asks if he wants the chest at the beginning of the rift. He is then warned that taking the chest will make getting out harder than simply leaving. After using the first challenge rift in a save file, he doesn't appear again.
 * The chest contains various loot for the player, including an amulet, a power scroll, and Cells. As soon as the chest is open, the entrance to the stage is sealed and the player must travel to the end of the trap filled stage to escape from it. The rift is closed forever when the player leaves and cannot be entered again, until a new rift with a new trap course appears.
 * The stage is filled exclusively with wall-to-wall traps to hinder the player's progression out of this stage.
 * will reduce the damage of those traps as well.
 * Any items left in the rift will be teleported to the side of the original portal when the player leaves. This counts even for useless items, like the Prisoner's Collar.

Trivia

 * In earlier versions of the game challenges had far fewer traps but were full of enemies. The goal was to kill all enemies within a time limit without getting damaged by the enemies or traps.
 * There is no limit to the maximum number of challenge rifts that can spawn per run.