Some Portable 3 x 3 Chaco War Wargame rules produced by ChatGPT

As I mentioned in a recent blog post, I have been using ChatGPT to create a set of Portable 3 x 3 Chaco War wargame rules. They needed a minor amount of tweaking to improve the clarity of the rules but what follows is probably 90% ChatGPT and 10% me.

A 1933 map of Paraguay. The disputed area - the Gran Chaco - is shown shaded in pink.

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Portable Chaco War Wargame

A fast-play grid-based wargame representing the difficult jungle and desert warfare of the conflict.

1. Game Setup

• Map: A 3 x 3 (or larger) grid, covered with a mix of open areas, dense jungle, dry scrub, and fortifications.
• Units: Infantry, Machine Guns, Mortars, Cavalry, Artillery, Air Support, and Commanders.
• Command & Control: Each side has a Commander with randomly-generated number of unit activations per turn.
• Fog of War: Hidden movement represents surprise attacks in difficult terrain.

2. Turn Sequence

• Command Phase: Each side rolls a D6 die to determine the number of units that can be activated this turn (each side activates that many units).
• Movement Phase: Activated units move one or two grid area, unless slowed by terrain.
• Combat Phase: Activated units may fire or assault enemy units in adjacent grid areas. (Defending units can fight back.)
• Morale Phase: Units check morale if they have been hit twice or more.
• Supply Phase: Check supply lines (units without supply suffer penalties).

3. Units & Special Rules

Unit	Move (in grid areas)	Weapon Range (in grid areas)	Attack Value	Defence Value	Special Rules
Bolivian Infantry	1	2	2	3	Well equipped, but suffers if moving through jungle. D6 die sore of 3, 4, 5, or 6 needed to move through jungle.
Paraguayan Infantry	1	2	2	3	Better adapted to the terrain; gains +1 Defence in jungle.
Machine Guns	1	3	4	3	May not move and fire in the same turn.
Mortars	1	3	4	3	May not move and fire in the same turn. Can fire over obstacles, but have limited ammunition (D6 die mortar rounds per gun).
Cavalry	2	1	2	2	Can move after attacking (this represents their ability to hit-and-run),
Artillery	1	4	3	2	May not move and fire in the same turn. Can fire over obstacles, but have limited ammunition (D6 die artillery rounds per gun).
Air Support	-	-	3	-	May be used once per battle. May only target non-jungle grid areas.
Fortifications	-	-	-	+2	Provides cover bonus.
Commanders	2	-	1	1	Boosts morale by adding +1 to morale of any unit in an adjacent grid area..

4. Combat

• Both players roll a D6 die and add and subtract their attack/defence values and any modifiers.
• Higher roll wins; loser is hit.
• If the result is a tie, both units are hit.

5. Special Features

• Hidden Movement & Ambushes
• Each side may place dummy counters in jungle/scrub grid areas.
• Units are revealed only when spotted by a unit entering an adjacent grid area and rolling a D6 die score of 4, 5, or 6.
• If an enemy unit moves into a grid area occupied by an enemy unit they have not spotted, they suffer -1 from their defence value.
• Supply & Attrition
• Each unit must be able to trace an unimpeded path to a supply base.
• If cut off for two turns, units suffer -1 on attack values and movement distance.
• Capturing enemy supply base restores half a D6 die score (rounded down) of lost units.
• Morale
• If a unit has taken two or more hits, roll a D6 die:
• 1, 2 or 3: Unit retreats a grid area.
• 4, 5, or 6: Unit holds position.
• Commander in adjacent grid area +1 to any D6 die score.
• Weather Effects
• At the start of each game, roll a D6 die for weather:
• 1 or 2: Extreme Heat: Reduce all movement by 1 grid area.
• 3 or 4: Fog: Ranged attacks suffer -1 attack value.
• 5 or 6: Normal Conditions: No effect.

6. Campaign & Scenarios

• Scenario 1: The Battle of Nanawa (1933)
• Bolivian Objective: Capture Paraguayan defences within 6 turns.
• Paraguayan Objective: Hold the position or repel attackers.
• Special Rule: Paraguayan defenders are fortified and get +1 defence value.
• Scenario 2: Guerrilla Warfare in the Jungle
• Bolivian Objective: Escort a convoy across the jungle to supply a fort.
• Paraguayan Objective: Ambush and destroy at least 2 Bolivian units.
• Special Rule: Paraguayan forces start hidden, Bolivians must scout carefully.
• Scenario 3: The Fall of Fort Boquerón (1932)
• Bolivian Objective: Break through Paraguayan lines before turn 5.
• Paraguayan Objective: Defend the fort; if it falls, retreat to fight another day.
• Special Rule: Mortars and artillery have limited ammunition (D6 rounds per gun).

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It is interesting to note that ChatGPT has taken into account the terrain found in ther Gran Chaco and the differences between that Bolivian and Paraguayan infantry. The former were mainly drawn from the Bolivian Altiplano (which is a high semi-arid and arid plateau with a cool and humid climate) and the latter were mainly Guarani who were used to living in the semi-arid, broadleaf jungle and scrub-covered lowland terrain found in the Gran Chaco.