Single vs. Multiplayer RPG Designs

tim-cain game-design rpg multiplayer single-player mmo pvp quest-design

Abstract

Problem: What are the fundamental design differences between single-player and multiplayer RPGs, and is a solo RPG an "incomplete design" compared to multiplayer?

Approach: Tim Cain draws on his experience shipping Arcanum (which had both single and multiplayer) and six years working on the MMO WildStar to break down the pros and cons across design, code, art, and testing.

Findings: Single-player and multiplayer RPGs are separate design spaces with significant overlap but distinct strengths. Single-player excels at reactive storytelling, unique player roles, and design simplicity. Multiplayer enables shared experiences, coordinated gameplay, and emergent social dynamics — but at massive cost in complexity across every discipline.

Key insight: Single-player RPGs are not incomplete multiplayer designs. They are distinct design spaces — each enables experiences the other fundamentally cannot.

Source: https://www.youtube.com/watch?v=CtTF0PQh-Oc

1. Context and Credentials

Tim answers a viewer question from "Games by Mark Wolf" asking about the pros and cons of solo vs. multiplayer RPGs, and whether a solo RPG is inherently an "incomplete design." Tim clarifies this is different from his earlier video about solo vs. party-based single-player games — this one is about single-player vs. multiplayer (multiple human players). His experience includes Arcanum (which shipped with both modes) and six years on WildStar as programming director and then design director.

2. Pros of Single-Player RPGs

Tim organizes the advantages into four categories: design, code, art, and testing — with design having by far the most entries.

2.1. Design Advantages

Reactive, player-centered storytelling. You can build a story that reacts to just one person. The player can be special or even unique — "the chosen one." You cannot do this in an MMO where a thousand chosen ones are all fulfilling the same prophecy simultaneously.

Simpler quest design. In multiplayer, you must handle players at different stages of quest completion. Tim gives the example of recovering a magic dagger: if one player already has it and a friend shows up wanting the same quest, the game must decide — can they share credit? Does the second player need their own dagger? Does the first player restart? Every solution will displease some players. In single-player, the problem doesn't exist.

No player-quit cascading failures. Tim shares an EverQuest story: his group fought through an entire dungeon floor to reach a locked door, and the player holding the key quit before they got there — wasting everyone's time. Single-player games simply pause or end when the player leaves.

Turn-based combat and deep dialogue. You can have turn-based combat or long one-on-one NPC dialogues — design elements that focus all attention on one player. Try turn-based combat in an MMO with a thousand players: "one person gets into combat and everybody waits." This is why MMOs invented instancing — temporarily converting the game into a small multiplayer or even solo experience.

Unique player abilities. Single-player games can give players abilities like knockouts, stuns, and one-hit kills that would be miserable in PvP. Without multiplayer, you avoid the mess of maintaining two rule sets — one for PvE and one for PvP — which Tim calls "very confusing very fast."

No griefing. Tim emphasizes this strongly: "Do not underestimate how much griefing has to be planned for in multiplayer games." If players can drop items, talk to each other, or interact at all, griefing can happen. He gives the example of a player luring a newbie into a dangerous zone with false promises of safety. Single-player eliminates this entire category of problems — and all the design, code, art, and testing time spent on anti-griefing systems.

2.2. Code Advantages

Simpler overall. Simpler design leads to simpler code. Beyond that:

  • Simpler AI — no need to split focus across hundreds of players or manage AI ticks for creatures spread across a massive world. Tim describes how Arcanum demand-loaded the world map and had to budget CPU cycles for creature AI. In multiplayer, players spread out "like gas in a container," activating AI everywhere simultaneously.
  • No networking code — networking programmers are specialists and hard to find. Single-player doesn't need them.
  • No instancing — no need to spin up duplicate dungeons.
  • No server infrastructure — no banks of servers, no load balancing, no cross-server coordination, no login management.

2.3. Art Advantages

In first-person single-player games, you may need zero PC animations. In third-person, far reduced detail is acceptable. In multiplayer, other players see each other — so every action (lockpicking, opening doors, using portals) needs visible, polished animations.

2.4. Testing Advantages

Single-player testing is dramatically simpler. No group testing across different party sizes (2, 3, 5, 10 players). No server-wide stress tests with thousands of simultaneous logins. Tim recalls an MMO launch where a thousand new players spawned in a non-instanced area and couldn't even see the NPC they needed to click — "it was just a mass of people."

3. Cons of Single-Player RPGs

No shared experience. You can't play with friends. Tim acknowledges this is a huge con — many modern players expect to play with friends.

Limited encounter scope. You can't design fights requiring tight coordination between multiple humans. Puzzles that need simultaneous actions (pulling three levers at once, hitting a monster with fire, frost, and shock simultaneously) don't work well in single-player — even real-time-with-pause introduces delays between character actions.

Unseen content. Unless you allow jack-of-all-trades characters with no level cap, players will miss content paths (stealth routes, speech options) because they can't build a character that does everything. Some players refuse to buy games where they can't see all content in one playthrough.

Less replay value. Multiplayer inherently increases replayability through different people, classes, servers, and rulesets. Single-player has to earn its replay value through design alone.

No PvP. While avoiding PvP is an advantage in some ways, it's also a loss. Tim quotes the PvP perspective: "I've never met more clever adversaries than fighting other people. No AI can ever be as clever as other people."

4. The "Incomplete Design" Argument

Tim directly disagrees with the premise that a solo RPG is an incomplete design. That argument assumes multiplayer encompasses everything single-player offers plus more. Tim's analysis shows the opposite: they are separate design spaces with a lot of overlap, but each enables experiences the other cannot. Single-player shines at things multiplayer struggles with, and vice versa.

5. References