DRN: the dice behind most rolls

What the game's open-ended dice roll is, how often it lands in each range, and which side a tie favours.

verified 6.37updated 2026-09-23 · Jake4 min read

When two numbers meet in a battle (an attack against a defence, a blow against armour, a spell against a resisting target), each side usually adds a DRN to its own value, and the two totals are compared. This page covers the roll itself: how it is made, how its results are spread, and what happens when the totals come out equal.

Making the roll

Throw two six-sided dice. A die that shows 1 to 5 keeps that value. A die that shows 6 is worth 5 instead, and it is thrown again, with whatever comes up added on. If the new throw is also a 6, the same thing happens again, for as long as the sixes keep coming. Then the two dice are added together.

Because a single die can keep going, the DRN is an open-ended roll: there is no highest result, only results that get less and less likely.

That die came up 6 twice before it settled on a 2, so on its own it is worth 12. The second die is added to that.

One die on its own

A few rolls use one open-ended die instead of two. The game writes that roll in lower case, as a drn, to keep it apart from the two-dice DRN.

How often each range comes up

The site computes these charts from the rule above. Nobody typed the percentages in, so they cannot drift away from it.

A single open-ended die:

Most single dice stop at the first throw. A result above 10 needs at least two sixes in a row.

The full DRN, two dice:

The totals bunch up in the middle, but the tail to the right never quite reaches zero. That is the reason for the design: an outcome that looks hopeless on paper still turns up now and then. Very little in the game is impossible; a great deal of it is merely unlikely.

Our own tests agree with the chart. The dice in the game’s damage and protection rolls come out spread the way it shows, not the way plain dice would, and not as if a six simply counted as six. Measured · n=15,792

Ties

Two totals can come out equal, and which side a tie favours depends on the roll.

• An attack hits only when its total is higher than the defence total. A tie is a miss.
• Damage wounds only when its total is higher than the protection total. A tie does nothing.
• A spell that magic resistance can stop works the other way round. The caster’s penetration total gets through when it at least equals the target’s resistance total, so the caster wins a tie.

So when two evenly matched sides roll against each other, the side that has to beat the other wins a little less than half the time. The ties go to the side that only has to hold.

A worked example

An attacker swings at a defender whose defence skill equals the attacker’s attack skill. The skills cancel, so only the dice matter.

The attacker’s first die shows 4. The second shows a 6 and is thrown again:

That is 4 + 8, a total of 12 on top of the attack skill.

The defender’s first die shows 1. The second shows two sixes before it stops:

That is 1 + 11, also 12 on top of the same skill. The totals are equal, the attack has to be higher to hit, and so the blow misses.

Where this comes from

The roll and its lower-case form are described in the manual’s chapter on the basics. The rules for hits, damage and ties are in its chapter on combat, and the spell rule is in its chapter on magic.