Nuclear Risk Diplomacy is a fast-paced strategy game where threat and bluster are a key part of the gameplay. While played on the Diplomacy board with the same pieces, it’s quite a different game where the combat is more Risk like, and of course there’s also the nukes.

A single nuclear weapon lays waste to an entire region (and the forces in it) and can be played at any time. But do you use them as weapons to get ahead or keep them as a deterrent to stop people using theirs on you? Should you build nukes or armies? With nukes you can eliminate another player at will, but then you’ll have nothing to defend yourself with when the other players’ armies roll over your borders. It’s all about maintaining the balance of terror!

I have no idea where this game came from or who created it. I was taught it in the late 1980s by some friends. These are the rules as I remember them and you’ll need to know the Diplomacy rules to understand them. Please send any comments to thomas@thomasbeagle.net

Requirements

• Standard Diplomacy set.
• 15 two-sided counters to represent nuclear weapons (nukes). Coins are ideal.

Setup

Set up board according to the Diplomacy rules.

Use the Diplomacy rules to choose which countries are playing (according to the number of players) and then randomly assign them to the players.

Allocate two nukes to each player. These should be placed on the coloured country name tags on the edge of the board. The stockpile of unallocated nukes are placed on Iceland.

Method of Play

Turns in NRD are either spring or fall. The game starts with spring and then alternates between them. (You may wish to use an indicator so that people don’t get confused.)

Choose a player to start the first turn. The start then rotates clockwise around the players changing each turn.

Each player in turn then moves their units, resolving any attacks as they go. The player gets to decide the order in which they move their pieces. Each unit can only be used once per turn.

Building Units and Nukes

At the end of the fall turn players get to build/lose army/navy units to match the number of supply centres they control. They must control at least one of their home supply centres to be able to build.

Building/reducing units happens at the end of the fall turn, in exactly the same way as in Diplomacy – except that you can also build nukes. Building a nuke requires two supply centres. A player cannot build a nuke if there are none available.

Nukes that have already been added to a player’s arsenal do not need to be supported by supply centres.

Playing Units and Combat

Units (army/navy) can move to an adjacent region, support an attack by another unit or stay where they are. Convoying (armies being transported by one or more fleets) works the same as in Diplomacy. There is no supporting defense.

Battles result when one unit (possibly supported by others) tries to move into a region already occupied by an opposing unit. The attacking player and the defending player roll a D6 for each piece involved, with the highest roll being the winner (draws are resolved in favour of the defender).

If the attack fails, nothing happens. If the attack succeeds, the defending player’s unit must retreat to an adjacent unoccupied region chosen by the defender (not the one where the attacker came from). If there is no where to retreat to the unit is destroyed.

Support

A unit can support the attack of another unit if the supporting unit is in a position where it could also move into the attacked region. Each supporting unit gives the attacking play an additional D6 to roll. Note that dice rolls are not added – if the attacker attacks with two armies and rolls a 2 and a 4 while the defender rolls a 5, the defender wins.

Playing Nukes

Nukes are played by placing them on a region of the board. This can be done by any player at any time.

The region is then contaminated and is impassable.

Supply centres that have been nuked cannot be used to support units and cannot be built on.

Nukes cannot be played at half-strength.

Mutants

If a unit is in the region when it is nuked, there is a 1 in 6 chance that the unit will spawn mutants. The player that the unit belongs to rolls a D6 and mutants are spawned if a 6 is rolled. The player then removes the nuked unit and places three additional units of their choice in regions adjacent to the nuked region.

Mutants are then treated as normal units. If you nuke your own army and get mutants, you may then move them as normal in that turn.

Nuke Clean Up

Regions contaminated by nukes can be rehabilitated by moving two units into them (at the cost of the units). Moving one unit in kills the unit and sets the contamination to half-strength (flip the coin representing the nuke). Moving a second unit into the region kills the unit, removes the contamination, and the nuke is returned to the stockpile.

A cleaned up supply centre does not belong to any player. (Therefore, to clean up a supply centre and take it you must move two in to clean it up and then move another in to take it. This can all be done in the same turn.)

Elimination and winning

Players are eliminated after losing all of their armies/navies, nukes, and home supply centres. Note that a player who has no armies or supply centres, and therefore cannot win, can still stay in the game and use their remaining nuclear stockpile to exact revenge.

The game is over when one player has control over half of the supply centres (18 supply centres out of 34) at the end of the fall turn, or when all other players are eliminated.

Variations

Vary the number of nukes allocated to the players at the start.

Vary the number of nukes in the game.