RISK for Two Players: The Neutral Army Rule Explained

In classic two-player RISK, a third of the board belongs to a neutral army that never attacks. In CONQUEST there is no neutral army: the two players split the whole map 50/50, with 40 armies each.

That one difference changes the opening. On the 42-territory World map you start with 21 territories instead of 14, and on average across our 15 maps 92% of your starting territories touch an enemy.

CONQUEST is a RISK-style game and is not affiliated with Hasbro, the maker of RISK. Everything below about CONQUEST comes from its rules engine, and everything about the board game comes from the sources linked next to it.

The board game deals a third of the map to nobody

The two-player rules as UltraBoardGames sets them out go like this. You remove the Secret Mission cards and the two wild cards, deal the territory cards into three equal piles, and take one pile each. The third pile is the neutral army. Each of you puts one army on each of your 14 territories, and one neutral army goes on each of the 14 remaining ones.

Then you place the rest. Players take turns putting two of their own armies on territories they hold, followed by one neutral army on a neutral territory of their choice, placed to block the opponent's advance.

The neutral armies have three rules. They never attack. They never receive reinforcements during the game. When you attack a neutral territory, your opponent rolls the defending dice. You win by eliminating your opponent, and you do not have to clear the neutral armies. Wikipedia's summary of the game agrees: the neutral army only plays defense, never attacks or moves, and has no turn.

Those rules exist for a reason you can see in the map. A two-player board is mostly empty space, and the neutral armies fill it with a buffer so the two of you do not collide on turn one.

CONQUEST has no neutral armies

The CONQUEST engine (newGame in shared/engine.js) takes a list of players and deals every territory to one of them. With two players, each gets half of the map and 40 armies. Territories are dealt round-robin, so the shares differ by at most one. Every territory starts with at least one army, and the remaining armies are scattered at random over your own territories.

There is no third owner and nothing to clear. You win when the other player has no territories left, or in Capitals mode when you hold every capital at once.

On the World map that is 21 territories each and 40 armies, so the board starts at about 1.9 armies per territory. The board game starts the same 40 armies on 14 territories, about 2.9 per territory, with a neutral army in between.

92% of your territories touch an enemy at the start

We measured the effect on the real engine and the real maps. For each of the 15 CONQUEST maps we dealt 3,000 two-player games, then counted which share of a player's starting territories are next to at least one enemy territory.

As a comparison we also took a hypothetical board-game deal on the same maps: territories shuffled into three equal thirds, one of them neutral, and we counted the share of your territories that touch your opponent. CONQUEST does not play this way. The second number only shows how much a neutral buffer removes.

Map	Territories	Yours at start	Armies per territory	Touch an enemy	With a neutral third	First turn reinforcements
British Isles	18	9.0	4.4	94%	81%	4.0
Germany	18	9.0	4.4	94%	83%	4.0
Japan	22	11.0	3.6	91%	78%	5.5
Europe	27	13.5	3.0	91%	78%	4.8
Asia	30	15.0	2.7	95%	84%	5.5
Russia	32	16.0	2.5	90%	79%	5.8
USA	39	19.5	2.1	94%	83%	6.6
World Classic	42	21.0	1.9	92%	79%	7.3

The mean over all 15 maps is 92% with no neutral army and 81% with a neutral third. Both are high. The neutral buffer takes out about one border in nine, not the whole front.

What the buffer really changes is what you can attack and who controls it. In the board game a third of your targets are armies your opponent defends on the neutral's behalf and can never reinforce. In CONQUEST every target is a real opponent who reinforces every turn. Our hypothetical number does not model the blocking placements the board game adds on top, so the real board-game buffer is probably thicker than 81% suggests. We did not measure that.

The script is scripts/research/conquest-two-player-neutral.mjs in the blog repository. The deals are random and the hypothetical thirds use a fixed seed, so a rerun of the first number moves by a point or less.

The first turn is the same race on every map

Turn 1 belongs to seat 1. It collects reinforcements before anyone else has moved, and the CONQUEST formula is your territories divided by 3 (minimum 3, rounded down), plus the bonus for every region you hold completely. The last column of the table is the average from our deals: 4.0 armies on an 18-territory map, 7.3 on World Classic, which includes the occasional region you were dealt whole.

Seat 1 attacks with those armies before seat 2 has placed one. We measured what that is worth at 74.1% for the first seat on the World map with equal Hard bots, in the first-move advantage post. The board game softens the start with a neutral army. CONQUEST relies on a manual draft or on swapping hosts between games if you want to even it out, and the draft guide shows that a draft makes the first strike worth even more rather than less.

What to do differently without a neutral buffer

These are recommendations from the numbers above, not rules from the game.

• Count your weak borders before you attack. With 92% of your territories touching an enemy, a stack of 1 on a border is a target for the other player's first turn.
• Expect an attack on turn 1 when you are seat 2. The first seat attacks before you place an army, so your thinnest border territories are the likely targets.
• Take a whole region early if the deal gives you most of it. The region bonus is added to your reinforcements every turn you hold it.
• Use a bot to practice the opening. The four bot levels differ in how willing they are to attack your thin borders, and Easy only makes 2 attacks a turn.

If you would rather play the neutral-army version, the board game or a faithful online version of it is the way to do it. We did not check which online versions implement the neutral army, so we cannot say which one does. For CONQUEST, a 2-player match runs in the browser at conquest.playfrontlines.com and the how-to-play page lists the rules. For other RISK-style options and where they are better than ours, see which RISK-style games need no account.