Rules¶

The Forest of Humbaba is played over 8 rounds with 2–4 players (4 recommended). Players compete to harvest cedars from a shared forest, but the forest is finite and its true depth is hidden. If it collapses, nobody wins.

Setup¶

Place the Forest Health marker on 6 (track: 0–10).
Shuffle the Forest Deck (30 cedars) and place it face down.
Place the Box Reserve (20 cedars) face down nearby.
Shuffle the Event Deck and set it aside.
Each player chooses an Archetype Deck (20 cards), shuffles it, and draws 5 cards for their starting hand.
Each player starts with 0 Capacity, 0 Patience, 0 Renewal, and 0 Stockpile.
The Stranger-King player takes the Defection Token, Cooperative side up.

Turn Structure¶

Each round has five phases, resolved in order:

1. Draw Phase¶

Each player draws 1 card from their personal draw pile. Skip on Round 1 (players already have 5 cards in hand).

2. Event Phase (Rounds 3, 5, 7 only)¶

Reveal the top card of the Event Deck. Apply its effects immediately, before the harvest phase. See Mechanics for the full event catalogue.

3. Harvest Phase (Simultaneous)¶

All players secretly select one card from their hand to play. Cards are revealed simultaneously and effects are resolved. Each player's total harvest is:

\[\text{Total harvest} = \text{Card's harvest value} + \text{Capacity tokens}\]

Forest Die Rolls

If the total harvest demanded exceeds the visible Forest Deck, the excess units are resolved one at a time via the Forest Die. Success draws from the Box Reserve; failure triggers immediate collapse. See Mechanics for the full probability table.

Players may negotiate, but the active player of each card decides targets for effects that mention "any player" or "target player."

4. Forest Step¶

Resolved in this order:

Regeneration. Move cedars from the Box Reserve to the Forest Deck equal to the base regen rate: \(\lfloor \text{Forest Health} \div 2 \rfloor\).
Renewal. Each player with Renewal tokens adds that many cedars from Box Reserve to Forest Deck, then discards those tokens.
Seneca Clip resolution. If a Seneca Clip was triggered last turn, reduce this turn's regeneration by 2. Reset the clip flag after.
Vacuum (Void) Effect. If exactly one player harvested 0 this turn, the player with the most Capacity (tie broken by Stockpile) gains +1 cedar from the Box Reserve into their Stockpile.

5. Cleanup Phase¶

Discard all played cards (they are gone for the game).
Reduce any temporary effect durations by 1 turn.
Check for collapse: if the Forest Deck is empty and all Forest Die rolls have failed, the forest collapses and the game ends immediately.

Forest Deck & Box Reserve¶

Pool	Starting Size	Visible?	Role
Forest Deck	30 cedars	Face down, countable	Visible commons stock — what players think is available
Box Reserve	20 cedars	Face down, never revealed	Hidden regeneration capacity — unknown to players

The Box Reserve feeds regeneration each turn. When the Forest Deck is empty and harvest is still demanded, the Forest Die determines whether cedars remain in the Box Reserve. The exact count of the Box Reserve is never revealed — even after the game ends.

Forest Health & Regeneration¶

Forest Health ranges from 0 to 10 and starts at 6.

Health	Regen Rate (cedars/turn)	Forest Die
7–10	3, 4, or 5 (⌊H/2⌋)	Collapse on 6
4–6	2 or 3	Collapse on 5–6
1–3	0 or 1	Collapse on 4–6
0	0 (no regeneration)	Collapse on 4–6

Health changes are caused by card effects (harvest damage, healing) and events (Humbaba's Wrath: −2). A drop of 2 or more in a single turn triggers a Seneca Clip.

Seneca Clip¶

Trigger: Forest Health drops by ≥2 in a single turn. Effect: Next turn's regeneration is reduced by 2. Reset: The clip flag clears after one turn of reduced regeneration.

This represents the asymmetric regen-shock dynamic of the Seneca Effect: a sharp coordinated over-extraction (or a catastrophic event) causes a disproportionate drop in regenerative capacity that compounds the damage.

Defection (Stranger-King Only)¶

The Stranger-King starts Cooperative. Any time from Round 3 onward, they may flip the Defection Token to Aggressive — this is irreversible.

Before defection: The Stranger-King accumulates Patience tokens and plays cooperative cards.
After defection: Patience tokens are spent for burst harvest (+1 per token) and extra Forest Health damage (+1 per token).
Mandatory defection: If not done voluntarily, defection occurs automatically at the start of Round 7.

End of Game & Victory¶

The game ends after 8 rounds or immediately if the forest collapses.

Outcome	Condition	Winner
Victory	Forest survives 8 rounds	Player with the most cedars in Stockpile
Pyrrhic Victory	Forest collapses at any point	No one wins — all players lose

Tie-breaking for Victory: most Capacity tokens → most cards remaining in draw pile → shared victory.

Quick Reference¶

Phase	When	Action
Draw	Every round (skip R1)	+1 card from draw pile
Event	Rounds 3, 5, 7	Reveal and apply event
Harvest	Every round	All players play 1 card simultaneously
Forest Step	Every round	Regen → Renewal → Seneca Clip → Vacuum
Cleanup	Every round	Discard cards, check collapse

Card Types¶

Each archetype deck contains 20 cards with diverse mechanics:

Type	Effect
`harvest`	Direct cedar extraction
`conditional_harvest`	Harvest that scales with Forest Health or player state
`sacrifice`	Return cedars to Forest Deck for healing or other benefits
`dual_mode`	Different effects before/after defection (Stranger-King)
`delayed_conservation`	Harvest now, heal later
`capacity`	Gain Capacity token
`information`	Reveal Forest Deck or Box Reserve count
`catastrophe`	Damage Forest Health
`trade`	Steal cedars from another player
`infrastructure`	Gain Renewal tokens
`institution`	Coordination reward or redistribution
`asymmetric_advantage`	Benefits conditional on wealth or Capacity threshold

See Archetypes for the full deck compositions.