The Chess Variant Pages

This page is written by the game's inventor, Jose Carrillo. This game is a favorite of its inventor.

Latrunculi XXI

Diagram 1 - Latrunculi (on 10x8 and 8x8 boards)

Latrunculi (Ludus latrunculorum or the Game of Little Soldiers) was an ancient strategy game played throughout the Roman Empire.

The Roman Empire in 117 AD, at its greatest extent

This colorful description of what is most definitely Latrunculi comes from a poem in Latin known as Laus Pisonis which was written by Saleius Bassus during the middle of the 1st century A. D.:

Cunningly the pieces are disposed on the open board and battles are fought with soldiery of glass, so that now White blocks Black, now Black blocks White. But every foe yields to thee, Piso; marshalled by thee, what piece ever gave way? What piece on the brink of death dealt not death to his enemy? Thousand-fold are thy battle tactics: one man in fleeing from an attack himself overpowers him, another, who has been standing on the look-out, comes up from a distant corner; another stoutly rushes into the melee and cheats his foe now creeping on his prey; another courts blockade on either flank and under feint of being blocked, himself blocks two men; another's objective is more ambitious, that he may quickly break through the massed phalanx, swoop into the lines and, razing the enemy's rampart, do havoc in the walled stronghold. Meantime, although the fight rages fiercely, the hostile ranks are split, yet thou thyself are victorious with serried lines unbroken or despoiled maybe of one or two men and both thy hands rattle with the prisoned throng.

Although Latrunculi resembles chess or draughts in some ways, it is generally accepted to be a game of military tactics. Because of the lack of reliable sources, reconstruction of the original game rules is difficult, and there are multiple interpretations of the available evidence. Latrunculi is believed to be similar or a variant of an earlier Greek game known as Petteia (a.k.a. Poleis, Cities or the Game of Pebbles).

Latrunculi and Petteia can be thought of as the Chess and Draughts of the Roman Empire and of Ancient Greece.

Latrunculi XXI is one of two ancient abstract strategy games that I reengineered in 2015 to introduce my son Joseph to the world of variants. My other variant, Petteia XXI, is played with the same rules as Latrunculi XXI, except for the fact that the Duxes (Kings) are removed.

Petteia XXI is not only a good alternative game for Draughts-variant lovers; but also a great training tool for Latrunculi XXI players, to get experience with moves and the tactics of the men, soldiers or pawns.

Diagram 2 - My son Joseph and I playing Latrunculi XXI and Petteia XXI, using Japanese Go stones to represent the soldiers, and 4-sided dice to represent the Duxes. We are using a 10x8 board for a cards game called Criblets.

Below are two Latrunculi XXI setups:

Diagram 3 - Position (8x8 board on left) after 8... g4-g3 - Francis Fahys vs Jose Carrillo, July 2016; and (right) my son Joseph playing OTB.

On the right above, Joseph and I are playing on a 10x8 board with tiny soldier figurines (representing Roman and Greek armies). The Duxes (Kings) are the ones with the red coats. All other pieces represent regular soldiers.

My objective when I created Latrunculi XXI was to make a set of rules and tactics for the ancient Roman game, which (leveraging my chess background) would allow a modern Latrunculi player to force a win on his/her opponent, therefore minimizing the number of draws, without relying on any serious mistakes in play by one side or the other.

Latrunculi XXI is a crossover variant which builds on the principles of the ancient Roman game and combines them with chess-like concepts, nomenclature, tactics and strategy to become a new Latrunculi Variant as well as a new Chess Variant.

At first the rules of Latrunculi XXI may seem long and complicated, but as you will quickly find out, the game is actually quite easy to play.

Learning to move the pieces is the easy part. Mastering the strategy and tactics needed to bring the opponent's Dux to its knees, is the real challenge of this variation of the ancient Roman game.


Diagram 4 - A 10x8 Latrunculi opening setup, displaying reverse symmetry

The Latrunculi opening setup is as follows: (on a 10x8 Capablanca board)

Dux (Leader or King) f2; Soldiers (or Pawns) a1, b1, c1, d1, e1, f1, g1, h1, i1, j1

Dux (Leader or King) e7; Soldiers (or Pawns) a8, b8, c8, d8, e8, f8, g8, h8, i8, j8

There is reverse symmetry between the two armies, similar to Chaturanga

Latrunculi XXI can be played on different size boards. The 12x8 Courier Chess board was likely the most popular board size used in the Roman Empire. But archeological findings show that the Romans may have used other board-sizes too.

Regardless of the size of the board, the general rule for the opening setup for Latrunculi is: Soldiers (Pawns) are placed on each of the players 1st-rank squares, and the Leader or Dux (King) is placed on the right square of the two middle squares in his/her 2nd rank. In the initial formation, you can see the brave Dux leading the charge of his army against the enemy formation.

Diagram 5 - Sample 12x8, 10x8 and 8x8 Latrunculi opening setups

A Latrunculi board itself is called the City, and the edges of the board represent the Walls of the city. The Walls of the City (the edges of the board) take an important role in the development of some of the battles in Latrunculi XXI.

When you play Latrunculi, picture yourself battling with your opponent inside a medieval walled city, like the one above. This one is Monteriggioni in the province of Siena in Italy.


All pieces (Duxes and Soldiers) move orthogonally any number of squares, just like Orthodox Chess Rooks. No diagonal moves are allowed. Pieces cannot jump other pieces.

However, unlike in Chess, captures in Latrunculi are done by custodial attacks, similar to how it's done in other games like: Hasami Shogi, by the pawns in Robert Abbott's Ultima or the rooks in Custodian Chess; a type of capture common to other games like Seega (Egypt) and the Scandinavian family of Tafl games.

A 2nd piece must move in to attack, by surrounding either horizontally or vertically, an enemy soldier (already in attack) to perform a capture.

Diagram 6 - Sample custodial captures

After white plays: d1-d5xc5 and black plays: ... De6-i6xi7 (right diagram), the c5 and i7 soldiers are captured and removed from the board.

However it is possible for a piece to move in between two men, without risking an immediate capture (or suicide) of the moving piece.

Diagram 7 - Soldiers moving safely between two enemy pieces: white plays i1-i6*, and black ... c8-c4

The '*' after white's move shows that the soldier blocked one of the sides of enemy black Dux

This time the soldiers at c4 and i6 are perfectly safe. The black soldier at c4 is said to be sandwiched-in, but this time (for the time being) is actually well positioned and has a relative fork on white's b4 and d4 soldiers, as with black's next move a8-a4 or e8-e4 (orange arrows), one of the two white soldiers will fall.

A situation that can occur in Latrunculi (but not in Chess) happens when a piece moves in such a way that more than one enemy soldier is captured. Look at the example below:

Diagram 8 - Dual Capture, positions after 13.j1-f1? (left) and after 13...h3-g3xf3xg4 (right), Arx vs Jose Carrillo, CV Game Courier, December 2016

The soldier at h3 moves to g3 and surrounds both of white's f3 and g4 soldiers (which are currently in one-to-one combats, and performs two custodial-captures at once. The notation for this move is: h3-g3xf3xg4

Since Latrunculi uses custodial captures (capture by surrounding) as the principal offensive tactic to capture enemy soldiers, it always takes at least two soldiers to perform a capture.

Diagram 9 - Sample custodial attacks and a corner attack

The example above shows the two soldiers (at d1 and g4) that can move to d4, surround and capture the enemy soldier at c4, who is already locked in a one-to-one combat with the b4 soldier.

A special type of custodial capture is shown at the top corner of the board. This time, the black j8 soldier is already in a one-to-one combat with the white i8 soldier. The white j5 soldier can play to j7 to surround the black soldier in the corner against the walls of the city, and to capture him. Remember! It takes at least two soldiers to capture an enemy soldier.


The goal of the game is to immobilize (the Roman's way to checkmate) or to Bare the opponent's Dux (King).

In Latrunculi XXI, stalemate is a loss for the stalemated player, there is 50-move draw rule and the Threefold Repetition rule gives a loss for the player forcing the 3rd repetition. A player left with a lone Dux loses the game.

Draws are discouraged in Latrunculi XXI. However, players can agree to a draw if they believe that the position merits that outcome. If the game goes for 50 moves without a capture, the game is automatically a draw.

Look at the sample immobilized Duxes below:

Diagram 10 - Sample immobilized (or checkmated) Duxes

The white Dux at i5 is surrounded in all four directions. The black Dux at a7 is also immobilized, but this time, since the black Dux has its back to the Wall of the City (edge of the board), it only takes three soldiers to immobilize him.

The black Dux at j1 is in one of the most vulnerable squares of the board for a Dux, a corner square. Having two sides already covered by the Walls of the City there, it only takes two soldiers to immobilize him.

Note that not all the soldiers surrounding (and therefore immobilizing) the Dux need to be enemy soldiers. The Dux can be the victim of a smothered mate when he is attacked by an enemy soldier, and his only escape paths are blocked by his own men.

How does the Ancient Roman way to immobilize an opponent compare to a traditional Chess checkmate?

Diagram 11 - An Orthodox Chess' checkmate and a Latrunculi immobilization

The objective in orthodox chess: to checkmate, is really to create an attack that causes the enemy King to be immobilized in a position where the King cannot escape the threat of capture. In the diagram on the left above, white attacks with the Rook (at d8) and immobilizes the black King in a position that he cannot escape from.

Similarly, the Roman way to checkmate also involves an attack that causes the enemy Dux (King) to be immobilized, but this time in a position where the Dux is "smothered" without any open paths available to flee. In the diagram on the right above, white attacks with the Soldier (at c8) to smother and immobilize the black King in a position that he cannot escape from. In Latrunculi there is no need to have a threat of capture to end the game. Blocking all of the Dux' adjacent orthogonal paths does the trick.

Interestingly, in both the Orthodox Chess and Latrunculi checkmate examples above, the paths for escape of the royal pieces are blocked by their own friendly pawns or soldiers.

Here is a sample checkmate from real play:

Diagram 12 - Position after 16.f6-f4#, Jose Carrillo vs Carlos Cetina, CV Game Courier, July 2016

The checkmate above is an example of a double custodial attack. White has two custodial attacks on the black Dux: the g3-Dux + e3-soldier and the f4 & f2 soldiers. The first custodial attack locked the black Dux to the f3-square (see rule 17 below), the f2-soldier partially-immobilized the black Dux (causing a check [by the d4-soldier] and creating a mating net); and the second attack completed by the white f4-soldier smothered the black Dux for the win.

To summarize, the rules so far (which also typically apply to the Classical Latrunculi game):

  1. The object of the game is:
    1. To immobilize or
    2. To Bare the opponent's Dux.
    3. However, it's illegal for a player to immobilize his own Dux.
  2. A player without any legal moves is stalemated and loses the game.
  3. All pieces move like Orthodox Chess Rooks.
  4. Pieces can neither play diagonally nor jump each other (like in checkers or draughts).
  5. Soldiers are captured by means of the custodial attacks tactic (moving in to surround an enemy soldier between two friendly pieces).
  6. A piece can move safely in between two enemy pieces, without being captured.
  7. Multiple soldiers can be captured in one turn. (example: creating multiple custodial capture situations with the same move)
  8. A soldier in a corner of the board can be captured if surrounded an attacked both vertically and horizontally.
  9. Captures are not mandatory. (just like in chess)

These rules provide the basics for an interesting new game. However, without a few additional new rules, a game played between two strong players will always end up in a draw, as the rules above do not allow a player to force a win on his opponent unless one of the players made several serious errors in his/her play. A game that can at best end in a draw (if well played) would be a boring game.

Since all pieces move like rooks, special rules exist in Latrunculi XXI to limit mobility or to allow special captures, otherwise games played with the classical rules could turn into drawish back and forth move affairs, where players try to maintain their soldiers on the diagonals, so as to avoid damaging their position. Look at this example:

Diagram 13 - Sample Classical Latrunculi diagonals-formation

With the reconstructed Classical Latrunculi rules, by keeping their soldiers in the diagonals, players can continue to move back and forth to protect their position, and the game would result in nothing but a lengthy and boring draw.

What follows now is my special set of additional rules that make Latrunculi XXI into a very playable game that does not depend on anyone making serious errors in play, and yet they give the game the spirit of a battle, just like any other Chess Variant.



New Latrunculi XXI Tactics:



  1. Locked Soldiers
  2. Push and Crush attack
  3. Flank attack
  4. Testudo formation and Phalanx attack
  5. Dux Mobility Rules (sides attacked)
    • 0 sides: Full mobility
    • 1 side : One step only
    • 2 sides: Only for offensive strikes
    • 3 sides: Can't move. Partially immobilized. (i.e. check)
    • 4 sides: Immobilized (i.e. checkmate)
  6. Quasi Check
  7. Check and Checkmate

Latrunculi XXI additional rules

Tactic #1 - Locked Pawns

Now look at the following position:

Diagram 18 - Sample blocked position

This is another type of situation that may occur in the classical Latrunculi, as well as in Latrunculi XX1 (even with the 3 new rules and tactics above). In order not to affect their positions, both players could move their free pawns at c7 and g1 almost indefinitely, and with so many squares available to each of the soldiers, it would take a long time before the game ended by means of the Threefold Repetition rule.

Positions like the above one inspired a new set of tactics called Charging Attacks. These new attacks allow the capture of soldiers to be achieved by means other than custodial attacks.

The list of Charging Attacks include:


Tactic #2 - The Push and Crush


Tactic #3 - The Flank Attack


Tactic #4 - Testudo and Phalanx formations



Below is a Latrunculi XXI setup, on a Capablanca 10x8 board. The Rooks on the outside of the corners of the board have no real significance (other than trying to weight down the vinyl board, to serve as the Towers of the City [the board], and as a reminder that all pieces move like Rooks).

Diagram 32 - Position after 10.Df5-f4 - Jose Carrillo vs Joe Joyce, CV Game Courier, July 2016

Game Notation

Given that all soldiers move the same way, long algrebraic notation is used to record the moves in Latrunculi XXI; because it may become confusing from where a soldier may have come from, to a particular square when recording a game; as potentially multiple soldiers can play to the same squares. Like for Pawns in Chess, Soldier moves do not need to have the initial (S) preceding the move. Only Dux moves need to carry the initial (D) in front of the move.

A move that threatens immobilization of a Dux carries the '+' sign (just like a check in chess), and a move that immobilizes and wins the game carries the '#' sign (just like a checkmate in chess).

Another symbol that is used in Latrunculi XXI is the '*', which represents a move that hits the enemy Dux (blocks one of his open orthogonal paths).

Another play that gets it's own symbol is the quasi check. If the move that hits the enemy Dux also partially-immobilises him, but does NOT place him in check, the "(+)" combination [including the parenthesis] is added to the end of the move.

If the move that hits the enemy Dux also puts him in "quasi check", "check" or "checkmate", the '(+)', '+' or "#" symbols are used by themselves, without using the '*'.

Therefore the notation for each move is: [D or blank][from square]-[to square](x captured piece square)[*, (+), + or #]

In Latrunculi XXI the terms immobilization threat and immobilization can be replaced by the common chess terms check and checkmate (or simply mate). To smother is also synonymous with to immobilize.

Diagram 33 - Sample Latrunculi XXI annotated moves:

  1. c8-c6xb6*
  2. d3-b3
  3. e2-e6+ (immobilization threat: d8-d7#)
  4. g3-g5*
  5. g2-i2#

Additional traditional Chess notation symbols can also be added to indicate the quality of the moves or the result of the game when annotating Latrunculi Games. (!, ?, !?, ?!, !!, ??, 1-0, 0-1, ½-½ )



Latrunculi XXI tactics for Chess Players







Sample Complete Latrunculi XXI Games

Game Courier Presets - Latrunculi XXI

Several sizes Latrunculi boards have been found in archaeological excavations. The game can be played on any one of the boards below.

Magnetic Chess Pieces: on 10x8, 12x8 or 8x8 boards

Draughts Pieces: on 10x8, 12x8 or 8x8 boards

Unchequered board with Go stones: on 10x8, 12x8 or 8x8 boards

Other Latrunculi sets:

By Carlos Cetina - Based on Chess Rooks, including a Royal Rook for the Dux: 12x8a and 12x8b:

Single Stone Latrunculi XXI

This game is the same as Latrunculi XXI, but without any Duxes. It is mean to be a training tool to the basics of soldier movement in Latrunculi XXI. When you double the number of soldiers you get Petteia XXI.

The game is played identically to Latrunculi XXI, but without Duxes. The objective of the game is annihilate the opponent's army and bring it down to either one or no soldiers left to battle, or to win by stalemating the opponent.

Game Courier Presets - Single Stone XXI

Magnetic Chess Pieces: on 10x8, 12x8 or 8x8 boards

Draughts Pieces: on 10x8, 12x8 or 8x8 boards


Petteia XXI

With the instructions of Latrunculi XXI, you actually get two games in one! If you ignore any provisions made in Latrunculi XXI for the Dux, and use the setup below, exclusively using soldiers, you get Petteia XXI.

The game is played identically to Latrunculi XXI, but without Duxes. The objective of the game is annihilate the opponent's army and bring it down to either one or no soldiers left to battle, or to win by stalemating the opponent. Beware of the Phallanxes in this game. They are common and deadly!


Game Courier Logs

Game Courier Logs for Games of Latrunculi XXI

Game Courier Logs for Games of Single Stone Latrunculi XXI

To see actual games that have been played on-line, follow the link above.


Latrunculi XXI and Petteia XXI were created by Jose Manuel Carrillo-Muniz, from Puerto Rico in 2015.


Chess Variants by the Author:

Other Presets by the Author:

Other Pages by the Author:

This 'user submitted' page is a collaboration between the posting user and the Chess Variant Pages. Registered contributors to the Chess Variant Pages have the ability to post their own works, subject to review and editing by the Chess Variant Pages Editorial Staff.

By Jose Carrillo.

Last revised by Jose Carrillo.

Web page created: 2016-06-12. Web page last updated: 2016-12-05