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Unearthed Arcana

COMPLEX SKILL CHECKS

pict With most skill checks, a single die roll immediately determines whether or not a character succeeds. If a character wants to jump across a chasm or recall a specific piece of information, his success or failure is apparent after a single check.

For complicated and time-consuming tasks (such as disabling a very complex trap or researching an obscure bit of knowledge), or at times when the game master wants to build tension and suspense, the complex skill check variant described here might be called for. In such a case, a specific number of successful skill checks must be achieved to complete the task. The complexity of the task is reflected in the DC of the required check, the number of successful rolls required to complete the task, and the maximum number of failed rolls that can occur before the attempt fails. In most cases, one or two failed rolls does not mean that a complex skill check has failed, but if three failed rolls occur before the character makes the required number of successful rolls, the attempt fails. Although three failures is a common baseline, game masters are encouraged to change the number if the situation warrants it.

The game master can also apply a penalty to future rolls in the complex check if the character rolls one or more failures. For instance, an intricate trade negotiation requiring a complex Diplomacy check might assess the character a -2 penalty on her checks for each failed check made as part of the complex check (representing the tide of the negotiation turning against her).

Table: Example Complex Skill Checks
Successes
Required
Complexity Example (Skill)
2 or 3SlightTraining a riding horse (Handle Animal)
4 to 6OrdinaryMaking a crossbow (Craft [weaponsmithing])
7 to 9GoodBypassing a fiendish trap (Disable Device)
10 or moreAmazingPick an amazing lock (Open Lock)

Each die roll is one portion of a complex skill check, and each die roll in the attempt represents at least 1 round of effort (it might represent more time, depending on the skill or task in question).

Like skill checks, ability checks can also be complex.

Complex skill checks are rarely used in situations that call for opposed checks.

BEHIND THE CURTAIN: HOW MANY SuCCESSES?
    During play, the game master will encounter additional situations in which complex skill checks may be appropriate. Two questions then arise: How high should the DC be, and how many successes should the task require? The answers to both of those questions depend on how great a chance of success the game master wants the players to have.

    Although making these determinations might seem daunting, the system for complex skill checks actually provides the game master a great deal of flexibility. Under the standard rules, game masters have only one tool to represent increasingly difficult tasks: increasing the DC. With complex checks, the game master can also use the number of successful attempts required to achieve overall success to control a skill check's difficulty.

TRYING AGAIN
Complex skill checks can usually be retried. However, like normal skill checks, some complex skill checks have consequences, and those consequences must be taken into account. (For example, a trap that requires a complex Disable Device check to disarm is triggered if the attempt fails, just as with a normal trap and a normal Disable Device check.)

Some skills are virtually useless for a particular task once an attempt to accomplish that task has failed, and this includes complex checks as well as regular skill checks. The Complex Skill Use section, below, describes which skills can be used in complex skill checks and which allow retries after failed attempts.

INTERRUPTING A COMPLEX SKILL CHECK
Most complex skill checks can be interrupted without adversely affecting the result of the check. However, the game master is free to rule that interrupting a specific check affects the result. At the game master's discretion, an interruption can count as one failed roll in the check's progression or can mean that the complex check fails.
AID ANOTHER
You can use the aid another action normally with complex skill checks. Characters aiding the character making the attempt must roll their aid another attempts each time the character makes a new die roll that is part of the complex skill check.
TAKING 10 AND TAKING 20
You can take 10 on a die roll during a complex skill check in any situation when you could take to on a normal check using that skill.

You can't take 20 when making a complex skill check. Taking 20 represents making the same skill check repeatedly until you succeed, but each successful die roll in a complex skill check represents only a portion of the success you must achieve to complete the skill check.

WHY COMPLEX CHECKS?
    Complex skill checks allow the game master to build suspense in critical situations, add tension to multiple-round tasks during combat, enhance special adventure-specific tasks, and resolve complex activities more quickly.

    To build suspense with complex skill checks, the game master can simply substitute a complex skill check for a normal skill check during a critical task. In most such situations, using a complex check lessens the likelihood that one failed roll will cause the party a significant setback.

    Complex skill checks provide a more balanced way of creating combat-affecting situations that depend on skill checks. For example, a complex Knowledge (architecture and engineering) check made to find the weak spot in a narrow stone bridge might allow the characters to collapse the bridge more easily and elude a group of powerful pursuers.

    Complex skill checks can also enhance adventure-specific or location-specific tasks such as disabling a particularly complex trap, appraising an extremely rare work of art, and so on.

    Complex skill checks let players resolve complicated situations with fewer die rolls. This is especially true of complex social interactions requiring multiple Bluff, Diplomacy, or Intimidate checks.

    Table: Chance for Success
    Required
    Roll
    Simple
    Check
    Complex
    Check (31)
    Complex
    Check (51)
    Complex
    Check (101)
    1. Number of successes required. (In each case, three failures ends the attempt.)
    2. If character can take 10, success is guaranteed.
    2295%99.88%99.62%98.04%
    6275%89.65%75.64%37.07%
    1150%50%22.66%1.93%
    1625%10.35%1.29%0.004%
    205%0.12%0%0%

    In most situations when the game master feels a complex skill check is warranted, it's appropriate for the DC of a complex skill check to match the DC of a simple check involving the same activity. This decreases the character's chance of achieving overall success, but because complex skill checks are used to best effect in tense situations and climactic encounters, increasing the difficulty adds spice to the scenario.

    Increasing the number of successes required always increases the difficulty of the task, but the degree of increase depends greatly on how likely the character attempting the check is to get a success each time he rolls the die.

    For example, Freeble has a Disable Device modifier of +14 and he encounters a trap with a DC of 25. Under the normal rules, Freeble has a 50-50 chance of successfully disarming the trap (because half of the possible results on a d20 are 11 or higher, granting her a success). If the trap requires a complex check to disarm, however, these odds can change. If succeeding on the complex check requires a certain number of successful die rolls before the same number of failures are recorded, Freeble's chance of overall success is essentially unchanged, but if the trap requires more successes to disarm than the number of failures required to fail the complex check, the chance of overall success drops. The more difficult it is for the character to meet or exceed the DC, the more pronounced the difference. If in the above example Freeble had a Disable Device modifier of +9 (meaning that he has to roll a 16 or higher to get a success), increasing the number of required successes reduces the chance of overall success much more rapidly.

    To determine the likelihood of overall success on a given complex skill check, compare the number that the character must roll on a d20 (obtained by subtracting the character's skill modifier from the check's DC) to the number of successes on Table: Chance for Success. By using this table to guide the choice of DC and number of successes, the game master can give two checks with an equal likelihood of success vastly different flavors.

COMPLEX SKILL USE
The following section provides general guidelines for using the complex skill check variant with each skill in the d20 game system.
Appraise

The Appraise skill seldom lends itself to complex skill checks. In rare cases, the game master might rule that a relic from a lost civilization or an extremely powerful magic item might require a complex skill check to appraise properly. In these cases, the DC and number of successes required should be determined by the game master specifically for the item in question.

Alternatively, if an item has a common value that is accepted in most of the campaign world but a drastically different value in one small portion of the setting, it might require one simple check to appraise the item's common value and a second, complex check (usually at a higher DC) to assess the item's worth in the specific area.

Balance
Since one Balance check covers movement over a short distance, using the skill does not lend itself to complex skill checks. Situations that call for multiple Balance checks always require multiple simple checks, not one complex check.
Bluff
Almost all uses of the Bluff skill require only a single roll to indicate whether or not you successfully fool an individual or a small group. However, in certain complicated social situations, a game master might want to speed the game along by requiring one complex Bluff check rather than many simple checks.

For example, one of the characters wants to spend several days in a noble's court trying to convince the people there that he and his adventuring companions are more capable than they really are. Rather than roleplay the many individual interactions, the game master decides to simulate this activity with a complex Bluff check. Because the nobles have heard little of the group's exploits, the game master sets the DC at 25 and requires that the player achieve five successful rolls before rolling three failures. Although this is a good simulation of the character interacting with a series of minor NPCs over several days, the game master still decides that interactions with a few individuals (the duke, his chancellor, and one renowned knight in the duke's service) are too important to incorporate into the complex check, and decides that the player should roleplay short encounters with each of the three and make separate, simple Bluff checks for each of them.

Climb
Because one Climb check covers movement over a short distance, using the skill does not lend itself to complex skill checks. Situations that call for multiple Climb checks always require multiple simple checks, not one complex check.
Concentration
Typical use of the Concentration skill never requires a complex skill check, but special circumstances might require complex checks as determined by the game master.

For example, the entrance to an enchanter's laboratory might be magically enhanced with mental barriers to entry and require a complex Concentration check to pass through.

Craft
Normal use of the Craft skill in many ways resembles a complex skill check, though it penalizes the character on each failure (rather than only after three failures).

You can replace the standard Craft check rules with a complex Craft check. In that case, a single failed check doesn't ruin one third of the raw materials; instead, rolling three failures before achieving the requisite number of successes ruins one third of the raw materials, requiring the character to start over. Each check represents a single day (if the item's value is no more than 1 gp) or a full week (if the item's value is higher than 1 gp) of work.

Table: Complex Craft Checks
Craft DC Successes
Required
9 or lower1
10-143
15-195
20-247
25 or higher10

Decipher Script
Complicated books, convoluted essays, or coded documents might require a complex Decipher Script check. When a character attempts to decipher an extremely long document, the game master can require one complex skill check rather than a simple skill check for each page. The DCs for complex checks follow the same guidelines that normal Decipher Script checks follow (DC 20 for simple messages, DC 25 for standard texts, and DC 30 or higher for intricate, exotic, or very old writing). Succeeding on the complex check requires that the character achieve one successful attempt for every ten pages of the manuscript before failing the check three times.
Diplomacy
Although typical use of the Diplomacy skill does not allow retries or lend itself to complex skill checks, a game master might choose to simulate an unusually long diplomatic session or interactions with multiple small groups for an extended period of time with one complex Diplomacy check.

For example, a character wants to convince a large and fractious group of merchants to suspend travel through a dangerous area for a short amount of time so that he and his companions can adventure in the area and confront the monsters there without exposing innocent travelers to danger. Instead of rolling thirty or more Diplomacy checks and roleplaying the reaction of each merchant in the group, the game master uses one complex skill check with a DC of 30 (representing the extreme difficulty of getting all the quarrelsome merchants to agree) that requires five successes before rolling three failures. The game master also might rule that because the tide of opinion can turn against the character very quickly in this case, each failed roil applies a cumulative 2 penalty to further rolls in the complex skill check.

Disable Device
Nearly any trap can be made to require a complex Disable Device check rather than a simple one. If the trap requires a large number of successes (six or more) or if the attempt is ruined by less than three failures, adjust the Challenge Rating of the trap up by 1 or 2 to reflect the greater difficulty of disarming the trap.

A trap that requires a complex skill check may have a higher cost and Challenge Rating than a trap of the same sort that only requires a simple check; see Table: Complex Disable Device Checks. See the standard rules for trap costs.

Table: Complex Disable Device Checks
Feature Cost Modifier CR Modifier
3 or more
successes
+250 gp per
additional success
(up to 6) or
+1 (7 or more)
3 failures+0 gp
2 failures+500 gp+1
1 failure+1,500 gp+1

Disguise
Although typical use of the Disguise skill does not allow retries or lend itself to complex skill checks, game masters might require that the disguised character make a complex Disguise check in the same complicated social situations that require a complex Bluff, Diplomacy, or Intimidate check.
Escape Artist
Although normal use of the Escape Artist skill does not lend itself to complex skill checks, a few specific environmental situations might call for a complex Escape Artist check. The most obvious of these and by far the most common is a long, extremely narrow passage that is only wide enough to let a character wiggle through. In this case, each successful roll made in the complex check represents navigating a portion of the passage, and a failed complex check means the character is stuck somewhere within the passage.
Forgery
As with Disguise, this skill rarely lends itself to complex checks, but in unusual situations where a forged document must go through the hands of several individuals, the game master might substitute a complex check for a simple Forgery check.
Gather Information
Typically, the Gather Information skill allows characters to get a general impression of major news items in a city or to find the answer to a specific question or information about a specific rumor. As long as the character has only a few questions or rumors to follow up on, a simple skill check should be used. In situations where the characters have half a dozen or more leads and questions to follow, the game master might want to use one complex skill check to resolve the information-gathering attempts. In this case, the number of successes required equals the number of questions or leads pursued, and the game master determines the number of failures that ruin the complex check.

In a complex Gather information check, each die roll represents 2 hours spent pursuing each individual question or lead.

Handle Animal
Complex skill checks work well with the extended training times that some uses of the Handle Animal skill require. When an animal is trained for a general purpose such as combat riding or hunting, it requires several weeks of work and one simple Handle Animal check under the normal rules. With the complex skill checks variant, this use of the skill always involves a complex skill check, with each die roll representing one week of training time. Rolling three failed results during the complex check means that the entire attempt fails and that training must begin again.

Table: Complex Handle Animal Checks
General Purpose Time DC Successes
Combat riding6 weeks206
Fighting3 weeks203
Guarding4 weeks204
Heavy labor2 weeks152
Hunting6 weeks206
Performance4 weeks154
Riding3 weeks153

Heal
Although normal use of the Heal skill does not lend itself to complex skill checks, game masters are free to require complex skill checks to treat particularly virulent strains of a disease or especially effective mixes of certain poisons.
Hide
Normal use of the Hide skill does not lend itself to complex skill checks. In certain unusual situations, a game master might use a complex skill check to simulate navigating an intricate environment such as an urban area while remaining unnoticed (this might mean blending in rather than remaining entirely out of sight in particularly crowded areas). For example, if a character wants to move from one place to another within a large city without being seen by members of the city watch, the game master might use a complex skill check to simulate the character's progress without having to determine the location of every guard or roleplaying each encounter.
Intimidate
Although typical use of the intimidate skill does not allow retries or lend itself to complex skill checks, a game master might choose to simulate an unusually complicated series of social encounters with one complex skill check in the same way that Bluff and Diplomacy can be used in such situations.
Jump
Since one Jump check represents one jump attempt, using the skill does not lend itself to complex skill checks. Situations that call for multiple jump checks always require multiple simple checks, not one complex check.
Knowledge
Researching rare or lost knowledge is an excellent use of the complex skill check variant.

To attempt a complex Knowledge check, a character must have access to a library that the game master decides is sufficient for the task. The game master is also free to rule that several successful rolls in a complex Knowledge check exhaust a particular library or tome's resources and lead the character to another work or library. In this way, a complex Knowledge check can become an adventure in itself as the character searches out rare or lost volumes of information.

Listen
Since one Listen check represents one attempt to hear something, using the skill does not lend itself to complex skill checks. Situations that call for multiple Listen checks always require multiple simple checks, not one complex check.
Move Silently
Using the Move Silently skill does not normally lend itself to complex skill checks, but a complex check can be used to simulate an unusually long period of moving silently in the same way that a complex Hide check might be used.
Open Lock
Although normal locks require only one Open Lock check, the game master is free to include locks or a series of locks that requires a complex check to open. (He can also rule that each casting of a knock spell counts as six successes toward opening a complex lock.) Particulars for complex locks are given in this table:

Table: Complex Open Locks Checks
Lock Quality DC Successes Price
Very simple20225 gp
Very simple20330 gp
Average25450 gp
Average25560 gp
Average25670 gp
Good307100 gp
Good308120 gp
Good309140 gp
Amazing4010200 gp

Perform
Normal use of the Perform skill does not lend itself to complex skill checks. At the game master's discretion, a few rare and powerful magic instruments might require a complex Perform check to activate.
Profession
Because each Profession check already represents a week of work, the use of the Profession skill does not lend itself to complex skill checks.
Ride
Normal use of the Ride skill does not lend itself to complex skill checks. A character performing a lengthy demonstration of difficult or trick riding, or competing in a race, might have to make a complex Ride check to pull off the entire show or finish the race; one roll per round is probably appropriate.
Search
At the game master's discretion, certain very well-hidden items might require a complex Search check to find. Usually this activity represents several individual Search attempts made in sequence and is typically better handled by treating each separate attempt as a normal Search check.
Sense Motive
Although typical use of the Sense Motive skill does not allow retries or lend itself to complex skill checks, a game master might choose to simulate an unusually complicated series of social encounters in a deceit-filled environment with a complex skill check like those described under the Bluff and Diplomacy descriptions.
Sleight of Hand
Normal use of the Sleight of Hand skill does not lend itself to complex skill checks. A character performing a lengthy demonstration of legerdemain (such as a magic show relying on sleight of hand) might have to make a complex Sleight of Hand check to pull off the entire show, one roll per 15 minutes is probably appropriate.
Spellcraft
Although use of the Spellcraft skill does not normally lend itself to complex skill checks, the game master is free to rule that examining a complicated magical effect might require a complex Spellcraft check.
Spot
Since one Spot check represents one attempt to notice something, using the skill does not lend itself to complex skill checks. Situations that call for multiple Spot checks always require multiple simple checks, not one complex check.
Survival
The game master might rule that a complex Survival check allows long-term survival in one type of climate or terrain, raising the required number of successes for extreme environments such as arctic regions or deserts.
Swim
The game master might rule that a complex Swim check allows a character to successfully swim for a longer period of time than I round. The amount of time each successful complex skill check allows the character to swim, along with the required number of successes and the DC, is given in Table: Complex Swim Checks. (The DC is slightly higher than for simple round-by-round checks to reflect the fact that the character is making many fewer checks.)

Table: Complex Swim Checks
Water Condition Successes Time DC
Calm water21 hour12
Rough water430 minutes18
Stormy water810 minutes25

Tumble
Normal use of the Tumble skill does not lend itself to complex skill checks. A character performing a lengthy routine of acrobatics might have to make a complex Tumble check to pull off the entire show. The frequency of the checks depends on the complexity of the routine.
Use Magic Device
Normal use of the Use Magic Device skill does not lend itself to complex skill checks. However, when a character makes a check to activate a magic item (especially a complicated one, or one with several different functions) for the first time, the game master might find a complex skill check appropriate. In very special cases, this check might require a full round of concentration per roll, but it should usually be part of the action required to activate the item.
Use Rope
Since one Use Rope check represents one attempt to manipulate a rope, using the skill does not lend itself to complex skill checks. Situations that call for multiple Use Rope checks always require multiple simple checks, not one complex check.