background Ludii Portal
Home of the Ludii General Game System


Home Games Forum Downloads References Concepts Contribute Tutorials Tournaments World Map Ludemes About




Category Board, Space, Group


Brood is a polyhex-matching game for two players – Black and White – played on an initially empty hexhex board. Michael Amundsen invented Brood in May 2022.


1 A group is a stone along with all stones one can reach from it through a series of steps onto adjacent stones of the same color.
1.1 The size of a group is the number of stones in it.

2 A brood is a group along with all other groups of identical color, size and shape. Shapes are considered identical across symmetries (just like in Bug).
2.1 The size of a brood is the number of groups in it.
2.2 The order of a brood is the size of the groups in it.
2.3 The mass of a brood is the number of stones in it (its size times its order).

On your turn, you must take one of the following two actions:
• Place 1 stone of your color
• Place 2 stones of a neutral color
Placement is always onto empty cells.

In this implementation,
(i) to place a piece of your color, you simply click an empty cell,
(ii) to place two neutrals, first click the neutral piece above the board, then two empty cells.

When the board is full, the player with the higher score wins.

For each of your broods, you score its mass multiplied by the lesser of its size and its order.

For example, if a brood consists of 2 groups of size 3, it is worth 12 points. Its order is 3, its size is 2 and its mass is 6. Since 2 is smaller than 3, the brood is worth 6*2 = 12.


Michael Admundsen

Creation date


Ludeme Description



Browse all concepts for Brood here.



     Contact Us

lkjh Maastricht University Data Science and Knowledge Engineering (DKE), Paul-Henri Spaaklaan 1, 6229 EN Maastricht, Netherlands Funded by a €2m ERC Consolidator Grant (#771292) from the European Research Council