Games that follow the Tak'Rahn Ruleset may include special events that require the player to "roll for luck". This means rolling a 1d50 die with up to three potential results: bad luck, good luck and no outcome.

By default, the bad luck outcome (if available) is triggered on a dice roll between 1 and 10, whereas the good luck outcome (if available) is triggered on a dice roll between 41 and 50. This results in a 20% chance of a bad luck outcome, 20% chance of a good luck outcome and a 60% chance of no outcome, assuming no luck modifiers are applied.

There are three types of luck modifier that can be applied to luck rolls. One is defined by the event and two are specific to the character for whom the luck event applies (see the sections below for further details). These three modifiers are combined and, rather than being added or subtracted from the dice roll, instead modify the default ranges for the bad luck and good luck events respectively. Positive luck modifiers reduce the bad luck range and increase the good luck range, while negative luck modifiers increase the bad luck range and reduce the good luck range. For example, a combined luck modifier of +2 would reduce the bad luck range to 1 to 8, while the good luck range would change to 39 to 50. A combined luck modifier of -2 would likewise increase the bad luck range to 1 to 12 while the good luck range would change to 43 to 50.

A combined luck modifier of +10 or more is sufficient to completely eliminate bad luck outcomes from an event, while a combined luck modifier of -10 or more is sufficient to completely eliminate good luck outcomes from an event.

Individual events may choose to influence the chance of a good luck event or bad luck event occurring by providing their own luck modifier. This modifier may range from -50 to +50, although values beyond +/-40 will guarantee the outcome as long as the character has no intrisic nor karmic luck modifiers to counteract the adjustment. This could for example be used to create an event where misfortune is almost guaranteed to befall a character, unless they have some protection by way of a positive luck modifier (or vice versa - a positive boon unless the character is intrinsically or karmically unlucky).

It is also worth noting that luck-based events need not necessarily include both good luck and bad luck outcomes; it is perfectly acceptable for an event to have only one of these available without adjusting the Event Luck Modifier. For example, an event with only a Good Luck outcome and no Event Luck Modifier will still trigger the Good Luck event if the 1d50 roll is in the range 41 to 50, however any roll from 1 to 40 will simply result in no event happening. Vice versa for events which contain only a Bad Luck outcome and no Event Luck Modifier. All luck-based events must still contain at least one of these outcome types however (Bad Luck or Good Luck), as to contain neither would result in the die roll having no purpose.

Intrinsic Luck Modifiers are any bonuses or penalties to luck rolls which are specific to that character, excluding Karmic Luck Modifiers which are explained in the section below. These are often referred to simply as modifiers to the character's hidden Luck attribute (hidden because this is tracked internally for each character by the Game Operative and is not displayed on the Character Sheet).

Bonuses and penalties to a character's Luck may be permanent or temporary in nature, for example a character might have a temporary blessing that provides +10 bonus to their Luck which applies only to the next luck roll.

The most common factor affecting a character's Luck is their Piety level. Characters with positive Piety levels gain bonuses to their Luck while characters with negative Piety levels gain penalties to their Luck. These bonuses/penalties persist for as long as the character's Piety level remains the same. The exact Luck modifiers for each Piety level can be found on the Alignment System page.

Aside from piety, the other most likely sources of Luck bonuses and penalties will come from item enchantments and temporary blessings/curses. In addition, all Halfling characters have a permanent +2 bonus to their Luck.

Due to the nature of randomness, it is entirely possible for streaks of positive or negative outcomes to occur through no fault of the player. Consequently, the ruleset allows for a system of tracking consecutive bad luck and consecutive good luck events to mitigate the chances of such streaks occurring.

The way this works is by keeping track of the outcomes of up to the most recent six luck rolls. When two or more of the most recent luck rolls have resulted in the same outcome, as long as that outcome was not Neutral/No Event, then a Karmic Luck Modifier is applied to that character according to the following tables:

Any time a neutral outcome occurs from a luck roll, or the outcome is opposite to the most recent roll before it (e.g. a Bad Luck outcome follows a Good Luck outcome), the Karmic Luck Modifier is reset to zero and the prior history of luck roll outcomes is discarded. The following contrived example illustrates how this might work:

1. The character rolls for luck and receives a Good Luck event. They now have one Good Luck event in their recent history; no modifiers are applied.
2. The character rolls for luck and receives another Good Luck event. They now have two consecutive Good Luck events in their recent history; their Karmic Luck Modifier is -1.
3. The character rolls for luck and receives another Good Luck event. They now have three consecutive Good Luck events in their recent history; their Karmic Luck Modifier is -2.
4. The character rolls for luck and receives a Bad Luck event. This is different to the outcome of the last event, so their recent history is purged and replaced with the current outcome. They now have one Bad Luck event in their recent history; no modifiers are applied.
5. The character rolls for luck and receives no outcome. This automatically purges their recent history regardless of what came before it.
6. The character rolls for luck and receives a Bad Luck event. They now have one Bad Luck event in their recent history; no modifiers are applied.
7. The character rolls for luck and receives another Bad Luck event. They now have two consecutive Bad Luck events in their recent history; their Karmic Luck Modifier is +1.
8. The character rolls for luck and receives another Bad Luck event. They now have three consecutive Bad Luck events in their recent history; their Karmic Luck Modifier is +2.
9. The character rolls for luck and receives another Bad Luck event. They now have four consecutive Bad Luck events in their recent history; their Karmic Luck Modifier is +4.
10. The character rolls for luck and receives another Bad Luck event. They now have five consecutive Bad Luck events in their recent history; their Karmic Luck Modifier is +7.
11. The character rolls for luck and receives another Bad Luck event. They now have six consecutive Bad Luck events in their recent history; their Karmic Luck Modifier is +10.
12. The character rolls for luck and receives yet another Bad Luck event. As their recent history is limited to six events, as far as the ruleset is concerned, they still only have six consecutive Bad Luck events in their recent history. Consequently their Karmic Luck Modifier remains at +10.
13. Finally, the character rolls for luck and receives no outcome. Their recent history is purged and their Karmic Luck Modifier is reset to zero.

Although the above example is unlikely to occur under normal circumstances, unless the character has severe penalties to their Intrinsic Luck or are triggering a lot of luck rolls with very wide Bad Luck outcome ranges, it shows how the Karmic Luck Modifier increases in magnitude in order to mitigate the chance of long streaks of a single non-neutral outcome type from occurring.

The following calculator can be used to model the effects of different luck modifiers and how that impacts the available ranges of each outcome, as well as the percentage chance of a given outcome based on those die roll ranges.