Thirty-two dwarfs. Eight trolls. One very old disagreement.
Speed and teamwork meet brute strength.
Swap sides in round two. Highest total wins.
Easy to learn. A lifetime to hold a grudge.
Two very different armies. One shared board. Learn Classic Thud in a few minutes.
32 dwarfs begin around the edge of a 165-square octagonal board. Eight trolls surround the central Thudstone. Dwarfs move first; players alternate turns. The stone never moves and blocks every piece.
A dwarf slides any distance horizontally, vertically or diagonally through empty squares. It cannot jump pieces or the stone.
An unbroken straight line of dwarfs can launch its front dwarf onto a troll, replacing it. Count the front dwarf too: three dwarfs can capture a troll up to three squares ahead. The path must be clear. A lone dwarf can capture an adjacent troll.
A troll normally moves one square in any direction to an empty square. After moving, it can capture any, all or none of the dwarfs in the eight surrounding squares.
An unbroken straight line of trolls can push its front troll up to as many squares as there are trolls in the line. It must land on an empty square beside at least one dwarf and capture at least one. It cannot jump anything.
Classic rounds end by agreement when useful captures have run out. In Thudd, use End round when you are ready to score; the computer accepts. A side with no pieces or no legal moves also ends the round here. Each surviving dwarf is worth 1 point, each troll 4.
Swap armies for round two. Add your surviving army’s points from each round. The higher combined total wins; equal totals are a draw. You may end a round early, so the score reflects the position you chose to stop in.
Click a piece, then a marked square. Dots show ordinary moves; outlined targets show hurls or shoves. After a troll moves, choose its captures and confirm. Undo takes back your turn and the computer’s reply; hints suggest a move without playing it. A canceled capture returns the troll to its original square.
Tab enters the board. Arrow keys move focus; Enter or Space selects; Escape clears the selection. Rotate changes the view. Your match and settings save in this browser. No account, server-side match, cookies, or analytics are used by the game.
Stronger levels examine more replies within a fixed time budget. All searches use a selection of promising moves; Expert is not an exhaustive solver or a rated engine. Hints use the Hard setting. Search runs in a Web Worker to keep the board responsive.
A forgiving opponent that explores freely and sometimes notices captures.
Prioritizes captures and formations, without looking ahead.
Searches up to 2 plies with a small set of promising moves.
Searches up to 3 plies with wider move selection (about 0.7 seconds).
Searches up to 5 plies within 1.8 seconds. Search depth depends on the position.
Classic rules are paraphrased from the original rulebook. Koom Valley is documented in the archive, and is not the ruleset on this board.
Original rulebook archive ↗From a very real tabletop to a wonderfully improbable world.
Trevor Truran designed Thud in 2002, with pieces sculpted by Bernard Pearson. Terry Pratchett supplied its name, wrote an in-world history, and later made the game part of Discworld. The licensed physical set is produced by the Discworld Emporium.
Meet the original game ↗Thud replays the old conflict between dwarfs and trolls at Koom Valley. Both cultures tell a different story of the battle. Playing both armies asks you to understand the other side.
The dwarfish name is Hnaflbaflsniflwhifltafl. Its resemblance to historical tafl games is part of the joke; Thud has its own asymmetrical movement and capture rules.
Explore the L-Space entry ↗The game appears in Going Postal (2004), where Lord Vetinari plays a distant opponent by clacks. It becomes central to Thud! (2005), the City Watch novel about the tensions surrounding Koom Valley.
Pratchett’s accompanying Thud — A Historical Perspective was collected as The Story of Thud in Once More* with Footnotes, then in A Blink of the Screen. The game is also mentioned in Unseen Academicals and Raising Steam.
The official Thud! synopsis ↗A faster variant accompanied the 2005 edition. It uses the same set with different setup, movement and objectives. Dwarfs escort a movable Thudstone to the far edge; trolls try to surround it with three trolls. It is a separate game. This board uses Classic Thud.
Read the contemporary preview ↗Thudd is an independent fan adaptation with original interface artwork. Discworld belongs to the Terry Pratchett estate; Thud was created by Trevor Truran. This game is not affiliated with or endorsed by the estate or the Discworld Emporium. Explore the official game to support its creators.