How to Run a One-on-One RPG Session Without Adding a Full Party of Sidekicks
When you have one player and one game master, you can run a satisfying session without assigning the player a roster of sidekick characters. Center the adventure on the player character, give them meaningful choices, and design obstacles that one protagonist can reasonably face. This guide focuses on preparing and running one session in a traditional tabletop RPG; the examples are system-neutral, with D&D encounter cautions where relevant.
1. Agree on the shape of the session
Before preparing scenes, ask what the player wants to do: investigate a strange lighthouse, escort a cart through a haunted wood, recover a stolen map, or negotiate passage into a walled town. Agree on tone, the kinds of scenes you both enjoy, and any content either of you would rather leave out. In one-on-one play, there is only one player’s attention and taste to serve, so a short conversation about expectations can prevent a session built around an unwanted kind of challenge. D&D Beyond’s duet-play guidance likewise recommends planning together and revisiting expectations as a campaign continues (New Player’s Guide: How to Play D&D One-on-One).
Make the agreement practical: “Tonight is a two-hour mystery with exploration and a short, avoidable fight.” That sentence gives you a useful boundary for preparation. It also helps distinguish a supporting non-player character (NPC), who appears in the fiction, from a sidekick who travels with the hero and acts as another adventurer. You can use the former without building the latter.
2. Give the hero a reason and a lead
Build the session around one clear reason the protagonist is involved and one lead they can act on. A retired cartographer might ask them to find a missing surveyor; the surveyor’s last note mentions a bell heard at low tide. The note is a lead, not a demand that the player follow one prescribed route. They could question the cartographer, visit the shore, or look for the surveyor’s boat.
Prepare two or three ways to learn important information. If the player misses one clue, another sensible route should keep the session moving. For example, the bell might be described in the note, heard from the harbor, or identified by a keeper who saw the surveyor leave. This is a practical design choice: it preserves player choice while keeping a single failed roll from ending the adventure.
Keep the protagonist at the center of the setup. D&D Duet’s advice for one-on-one campaigns describes the player character as the main character and recommends tying narrative elements to them (Start Your One-on-One D&D Adventure!). A personal connection can be as simple as the cartographer trusting this hero with the job because they once returned a lost instrument. It need not turn into an elaborate backstory revelation.
3. Prepare a compact sequence, not a party-sized plot
For a single session, prepare a starting scene, a few likely approaches, one complication, and a clear decision or payoff. Avoid writing a long sequence that assumes the player will choose a particular door or ally. A small situation with interacting pieces is easier to adapt than a string of scenes that only work in one order.
For the lighthouse example, your notes might be: the keeper’s locked store room; a tide chart with a gap; the surveyor’s skiff caught in rocks; and a bell that rings when a hidden sea cave floods. The complication could be that the tide is rising. The player can investigate the keeper’s records, repair the skiff, or seek a safe route to the cave. Each approach reveals something and changes what is possible next.
Prepare the people the hero may meet by giving each one a name, a goal, and one useful detail. The keeper wants the bell silenced because it disrupts the harbor; the cartographer wants the surveyor found. These NPCs can answer questions, bargain, or disagree without becoming a permanent companion cast. Their roles support the player’s decisions rather than taking over the adventure.
4. Make obstacles solvable by one protagonist
An obstacle should ask what the player does, not whether they brought the right extra character. A collapsed footbridge can be crossed by finding a safer route, making a rope line, or convincing a local ferrier to help. A locked cabinet might open with a key, a tool, or information that changes the keeper’s mind. Give different approaches different costs, risks, or clues so that the player’s choice matters.
When a character lacks a skill or resource, let that create a tradeoff rather than a dead end. If the hero cannot read an old chart, they might ask the cartographer for help, compare it with a harbor map, or make a risky guess about the route. That keeps the challenge in the fiction and avoids solving every gap by adding a sidekick with the missing ability.
Supporting NPCs can provide information, access, or temporary help, but keep consequential choices with the player. The keeper may point out that the tide is turning; the player decides whether to enter the cave. A local might hold a rope, while the player chooses when to cross. This preserves a small cast and keeps the hero’s actions driving the session.
5. Scale danger and combat carefully
A lone character has no party members to share attention, cover weaknesses, or recover them after a mistake. If you use a game designed for groups, check its assumptions before reusing an encounter. D&D Beyond notes that a group encounter can overwhelm a single character and recommends adapting the number or type of enemies; it also flags how exposed a lone character can be when incapacitated (How to Play D&D One-on-One). Those cautions concern D&D, but the broader preparation question applies to any system: what happens if the only protagonist loses a key roll or falls in a fight?
For a system-neutral session, reduce simultaneous threats, make the danger legible, and include a way to change the situation. At the lighthouse, one smuggler guarding the skiff creates a clear confrontation. Three opponents surrounding the character may leave little room for choices. The player could sneak past, bargain, set a distraction, or fight; the encounter does not have to assume combat is the only answer.
Decide in advance what defeat means in your game. A failed fight might cost time, equipment, or access to the cave, or leave the hero captured and facing a new choice. Use consequences that fit your rules and the tone you agreed on. Do not quietly import a party-sized combat’s lethality into a one-character scene without considering its effect on the session.
6. Use tools to fill uncertainty, not add more characters
If you are running a game with a defined oracle, random table, or resolution procedure, use it when the answer is genuinely uncertain and the result would help you make the next decision. Ironsworn is one published example of a game designed for solo, cooperative, and guided play; its rulebook includes oracle tables for narrative inspiration (Ironsworn Official Rulebook). Its procedures belong to that game, so treat it as an example of a tool approach rather than a universal rule for other systems.
You can also make a small, transparent table for your own session. For instance, if the player listens at the sea cave entrance, decide whether the sound is water, a bell, or a voice with a die roll. State what is uncertain before rolling, then interpret the outcome in context. If you already know the keeper is in the harbor, there is no need to roll to rediscover that fact.
7. End with a choice and a useful next hook
Give the player a decision that changes what happens next. At the lighthouse, they might rescue the surveyor and leave the bell ringing, or silence the bell and risk losing the surveyor’s trail. Neither option needs to be the “correct” solution. The player’s priorities should determine the outcome.
Close by asking what the character does after the immediate problem is settled. They might return to the cartographer, keep the chart, or investigate who placed the bell in the cave. That answer can become the next session’s starting point. If you are playing a one-shot, let the decision resolve the central question instead of forcing a sequel hook.
A quick preparation checklist
Before play, write down the session’s agreed tone and focus, the protagonist’s reason to act, a few leads, two or three NPC goals, a complication, and the consequences of failure. Check whether any danger assumes a larger party. During play, ask what the character tries, show the likely stakes, and let their choices redirect the prepared material. You do not need a full party of sidekicks to give one hero a vivid, playable adventure.