From the Game Rules:
The Pale Forest follows an expedition of humans that dive beneath the fog to explore the Forest and what may lie below.
Each character is represented with a Spindown d20. This represents their health, available resources and overall well-being. If it reaches 1, something bad happens.
In The Pale Forest, players roll against the GM to see if they get a positive or negative outcome on Challenges.
When a challenge occurs the player decides what a positive outcome would be and the GM decides what a negative outcome would be. The player then converts as much of their Resources into d6 as they would like (1 resource = 1d6). A player may opt to spend nothing and roll only a single d6. The player needs to beat the GM's house roll. The house roll starts as 1d6, but each time a player defeats the GM an extra 1d6 is added to the roll. When a player is defeated 1d6 is removed (minimum 1d6). The minimum number of d6 increases by 1 for each layer deep the characters are in the depths.
Whether the player wins or loses they permanently remove the number of d6 that they used from their total.