Roleplaying games typically do an excellent job of defining exactly what game skills and specific abilities can accomplish. However, a common dilemma arises at the table: what happens when characters who lack these applicable skills or abilities attempt something that reasonably ought to have a chance of success?.

Various RPGs define this default probability in different ways. Systems like Star Wars d6, Vampire: the Masquerade, and modern iterations of D&D simply have players roll against a corresponding attribute without adding a skill bonus. Meanwhile, games like GURPS, BRP, and the AD&D 1.5E survival guides offer defined base probabilities or limited capacities for unskilled attempts.

But there is an alternative, old-school philosophy: Fact-Based Mechanics. This approach utilizes plain, knowable facts in lieu of treating actions as unknowns that must be diced out through normal game mechanics. These facts can be specified in the RPG rules or found directly within the game data. When facts aren’t explicitly stated within the game, the system simply defers to real life. Advanced Dungeons & Dragons 1st Edition perfectly exemplifies this by using an “assumed medieval standard” to represent the average abilities of normal humans.¹ It establishes a paradigm where the RPG is driven first and foremost by imagination, pitting the wits and creativity of the players directly against the challenges of the game world. In this style of play, game mechanics merely serve as a backup or safety net for those moments when players find themselves at a loss for a clever solution.

Deconstructing Thief Abilities

To truly understand this approach, it is worth making the pedantic point that AD&D actually possesses no generalized skill or ability called “Stealth”. Instead, it features specific abilities like Move Silently and Hide in Shadows, which have highly specific applications.

• Moving Silently means exactly that: if the check succeeds, the thief moves with absolute silence, not merely quietly.^{2 3}While the thief might still be seen, smelled, or otherwise sensed, they cannot be heard. This absolute silence means they bypass the standard auditory detection distances, and they cannot be detected even if an opponent is actively listening and succeeds on their chance at Hearing Noise.
• Hide in Shadows does exactly what its name implies, and it is entirely different from simply hiding around a corner. If there is a physical obstruction blocking line of sight, absolutely no skill is required to remain hidden. Hide in Shadows allows a thief to remain unseen even when line of sight is completely unobstructed provided the thief is not under direct observation while going into hiding. This ability requires the presence of shadowy conditions, which implicitly rely on a combination of light and dark. While darkness allows thieves to hide from normal vision, it is the act of hiding behind or within the (heat-producing) light that lets them evade infravision.⁴

The Non-Thief Reality: Fact-Based Stealth

For non-thieves, avoiding detection is accomplished by leaning on established facts: remaining outside of hearing range and keeping outside of line of sight. Hiding behind objects or simply keeping a sufficient distance requires no special skills and no random dice rolls to successfully avoid detection. The Dungeon Masters Guide provides the relevant facts for this in its Pursuit & Evasion of Pursuit section.⁵

Visually, light can be seen at a nearly infinite distance in a straight line of sight, but any corner immediately reduces that visible distance to 60 feet. Auditory facts are also clearly defined: characters wearing metal armor can be heard up to 90 feet away, those in hard boots at 60 feet, and relatively quiet movement is audible at 30 feet. Scent is another factor; creatures that hunt or track using smell can detect normal scents for several hours, even within a dungeon environment. However, astute players can use facts to mask their scent with items like mustard powder, oil of citronella, or crushed stinging nettle.

Niche Protection and Party Synergy

This same logic applies to scaling obstacles. Thieves possess the “Climb Walls” skill, which should not be confused with general climbing ability. It is specifically meant for scaling up and down walls and vertical surfaces⁶ ranging from very smooth with few cracks to rough and with ledges.⁷ Because the rules only require dice rolls for the highly specialized Climb Walls thief function, the implication under the assumed medieval standard is that non-thieves can handle routine vertical movement like ladders and ropes reliably, without deferring to game mechanics, unless some special difficulty or hazard sufficient to stipulate a chance for failure is present.

Some game masters worry that allowing non-thieves to perform limited thief-like actions raises concerns regarding niche protection. One might assume that restricting climbing exclusively to thieves does more to protect their unique role. However, a thief who scales a wall to reach an area inaccessible to the rest of the party can accomplish far less on their own. When non-thieves can automatically climb ropes, it directly benefits the thief, who can climb up, lower a rope, and receive the backup needed to push forward into that inaccessible area. This dynamic amplifies the thief’s value to the entire party, turning a single character’s climb into a gateway that grants access to everyone, multiplying the effect of the thief’s unique ability.

Solving the Group Stealth Problem

A similar set of benefits and problems applies directly to stealth operations. In modern RPG thinking, when a group attempts to sneak into a location, it is almost certain that one party member will fail their stealth check, which negates the stealth ability for all, including the thief.

But under Fact-Based Mechanics, it is understood that the party remains undetected as long as they stay out of line of sight and hearing range. This allows the thief to go up ahead, utilizing their special skills to avoid detection, in order to scout and relay back to the party exactly where they can and cannot safely maneuver. Consequently, the success or failure of the mission rests on the thief’s skills, rather than being dragged down by the party’s weakest link.

Conclusion

When we stray from the specific, literal applications of thief abilities and instead generalize them into broad skills with unskilled default rolls, we are not actually doing the players any favors. This modern approach muddies the waters by stripping away the knowable, interactable facts of the environment and replacing them with abstract randomness. While giving everyone a fractional chance to sneak or climb might seem like providing more opportunities for success, the net result is almost always a setback for the party. Instead of allowing the group to bypass obstacles through logic and the specialized expertise of their most capable member—such as a thief scaling a sheer surface to lower a rope, or scouting ahead to map out safe, out-of-sight paths—generalized mechanics force every individual to roll the dice. Ultimately, this shifts the burden of success away from the party’s strongest asset and places it squarely on the shoulders of their weakest link, transforming what should be a tactical triumph into an inevitable mathematical failure. Ultimately, honoring the literal facts of the game world doesn’t limit the players—it frees them to succeed through teamwork and ingenuity rather than leaving their fate to the mercy of the dice.

But this is just one perspective on how to handle the ever-present tension between player creativity and game rules. When systems evolved to provide a standardized mechanic for every conceivable action, they inevitably shifted player focus away from the environment and onto the character sheet. I’d love to hear how these differing design philosophies and their consequences play out at your own table.

Join the Discussion:

• The Mathematical Trap: Have you experienced the “inevitable mathematical failure” of group checks at your table? Beyond just stealth and climbing, what are your most memorable examples of a brilliant party plan falling apart simply because the system demanded too many sequential dice rolls from the group?
• The Case for Universal Skills (The Flip Side): Do you prefer the modern approach of generalized skill checks? Is there an argument that giving every character at least a fractional chance to succeed feels fairer, or perhaps more heroic, than restricting specific, world-interacting actions to a single class?
• Designing for Facts: For the Dungeon Masters out there, how do you design your environments to encourage players to engage with the facts of the world (like lighting, noise, and architecture) rather than immediately reaching for their character sheets to look for a skill to roll?

1. DMG, pg 15. “a [Strength] score of 10 or thereabouts shows that the creature has the norm for a human adult male (based on an assumed medieval standard where the typical individual was in ‘good shape’ due to the necessity of hard labor)” ↩︎
2. PHB, pg 28. “Success means movement was silent.” ↩︎
3. DMG, pg 19. Moving silently is defined as “Silent movement.” ↩︎
4. PHB, pg 28. “[Hiding in Shadows] can be accomplished with respect to creatures with infravision (q.v.) only if some heat-producing light source is near to the creature of to the thief attempting to so hide.” ↩︎
5. DMG, pg 68. See notes for LIGHT, NOISE, and ODORS. ↩︎
6. PHB, pg 27. “Ascending and descending vertical surfaces is the ability of the thief to climb up and down walls.” ↩︎
7. DMG, pg 19. See WALL CLIMBING TABLE, FEET PER ROUND OF CLIMBING. ↩︎