How to Play Mycelia

Last Updated on April 7, 2025 by The Official Game Rules Team

Mycelia is a deck-building game where 1 to 4 players take on the role of mushroom enthusiasts in the Valley of a Thousand Dewdrops. Players aim to clear their forest game boards of magical dewdrops and seek assistance from the Goddess of the Forest. Here’s a breakdown of the rules.

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What is a Deck-Building Game?

In a deck-building game, each player starts with a small set of cards, known as a deck. Throughout the game, players enhance their decks by adding new cards to improve their options and strategies. The term “deck-building” comes from the combination of these two concepts: building and customizing your own deck as the game progresses.

A key feature of deck-building games is that players repeatedly use their decks in multiple rounds. On each turn, players draw a card from the supply, play it, discard it, shuffle their deck, and continue the cycle in the next round.

Game Setup

Place the shrine in the center of the table as shown. The shrine is where dewdrops are collected during the game. When it fills, new dewdrops are introduced into the game.
Position the supply die on the appropriate space of the shrine:
- In a 4-player game, place it on the “4” space.
- In a 3-player game, place it on the “3” space.
- In a 2-player game, place it on the “2” space.
Randomly select one supply card and place it next to the shrine. Put the remaining three cards back in the box.
Shuffle the 40 basic playing cards to form a face-down supply pile. Place the top 5 cards face-up in a row next to the supply pile as the open showcase for hiring new heroes.
Distribute the starting setup: each player receives a game board, 20 dewdrops placed on it as shown on the setup card, and 6 starting cards of the same type. Players shuffle their starting cards into their own supply pile and draw 3 cards to begin the game.

instruction manual explaining how to assemble the shrine in the mycelia board game

How to Take a Turn

Play Cards
On your turn, play all 3 cards in your hand. Place them in your discard pile one at a time, in the order you choose. You must immediately perform the function of each card before playing the next one. If you cannot or do not want to fully use a card, you must still play and discard it. Your main goal is to move dewdrops towards the shrine on your board, which will allow you to remove them. Additionally, you can collect leaves, which act as the currency for hiring new heroes and performing actions.
Hire Heroes (Buy Cards)
At any point during your turn, you can hire heroes from the open showcase by paying the required amount of leaves. New heroes are added to your deck and placed face-down on top of your supply pile.
Basic Actions (Action Cards)
In addition to playing cards and hiring heroes, you can perform basic actions, as indicated on the action cards below your game board. These actions can be done at any time during your turn, but only once per action card. For example, you can pay 1 leaf to refresh the showcase, or 3 leaves to move a dewdrop to an adjacent field.

End of Your Turn

Your turn ends when you have played all 3 cards and have no further actions you wish to perform. Then:

Place all played cards in your discard pile.
Fill the showcase with 5 new cards. If the supply pile is empty, shuffle the discard pile to create a new supply pile.
Check if the shrine is full. If it is, proceed to the shrine’s next steps for distributing new dewdrops to players.
If you removed any dewdrops during your turn, place them in the shrine field as instructed.

End of the Game

The game ends when a player removes the last dewdrop from their board. If multiple players clear their boards in the same round, the player with the most leaves left in their supply wins. If there’s a tie, all tied players win.

Card Functions and Symbols

Cards have functions explained through symbols, typically performed from left to right. Some cards allow you to choose between different actions (either/or), while others let you perform multiple actions (and). If a function has a symbol for other players, they can perform that action instead of you.

The Expansion

Once you are comfortable with the base game, you can introduce the expansion cards, which are identifiable by their special symbol. These cards add more complexity and variety to the game.

Shuffle the 30 new expansion cards together with the 40 existing hero cards. The showcase will still hold 5 cards as usual. Along with the hero cards, you’ll need action cards c, d, and e, which can be accessed by playing specific cards during the game. These action cards should be placed as an open supply.

Removing Cards

A new feature in the expanded game is the ability to remove cards (both hero and leaf cards) from your deck for the remainder of the round. This lets you get rid of weak starting cards or any cards you’ve acquired that you no longer need. When you perform a removal (or use a single effect—see below), search your discard pile and select the card to remove. You are not required to remove any card if you prefer not to. Removed cards are returned to the box and are out of play for the entire round.

Single Effects

Some expansion cards provide single-use bonus effects, which function similarly to card abilities. These effects are not activated when playing cards but occur once when you hire the hero. When you hire such a hero, immediately resolve the single effect (indicated by a lightning bolt in the top-left corner of the card). Afterward, the card is placed in your supply pile as usual.

Additional Action Cards

The single effects also grant you the 6 new action cards (c, d, e) included in the expansion. When you hire a hero that offers one of these cards, place it at the bottom of your game board. You are allowed to have the same additional action card twice (e.g., 2x c, 2x d, or 2x e), but you may only have a total of 4 action cards. If you acquire a 5th or more action cards, you must remove one and return it to the box.

An action card acquired this way can be used during the current turn, just like actions a and b. You may perform each action once per turn, and you must pay the corresponding leaf cost to use it.

Action c Pay 3 leaves from your personal supply to perform the following: Move any dewdrop exactly 1 field (orthogonally). If there’s another dewdrop on the same field, move it 1 field (orthogonally) as well. The second drop can be moved in a different direction from the first.

Action d Pay 3 leaves from your personal supply to remove 1 dewdrop from any field, even if there are more dewdrops present.

Action e Pay 3 leaves from your personal supply to remove 1 card from your discard pile. This action works the same way as the “Remove cards” rule.

Special Feature/Exception: Additional Shrine Field

The Clavulinopsis fusiformis card introduces an additional shrine field: When you hire this hero, select a field with exactly 1 dewdrop on it, remove the drop, and place the shrine field on this spot. This field no longer counts as a landscape and behaves like a second shrine field, removing any dewdrops moved onto it. You can have up to two additional shrine fields on your board if you hire this hero twice.

Examples:

If you purchase the Hydnum repandum or Tylopilus formosus cards, you can immediately remove 1 card from your discard pile. If you draw these cards again in future rounds, you cannot use this single effect again.
If you hire the Fomes fomentarius hero, all other players can immediately move 1 dewdrop from any field to a vertically or horizontally adjacent field, but you cannot. This single effect will not trigger in later rounds.