Having Unique Rules For Players

tim-cain system-design rpg player-npc-parity game-mechanics pvp pve

Abstract

Problem: In many RPGs, the player character operates under different rules than NPCs — immune to traps, able to fast-travel, pause time, or save-scum — creating a sense of inconsistency. Should designers strive to eliminate this divide?

Approach: Tim Cain examines which rule asymmetries are unavoidable, which are deliberate design choices, and which create friction, drawing on his experience with Fallout, Pillars of Eternity, The Outer Worlds, Arcanum, and Baldur's Gate.

Findings: A single unified ruleset for players and NPCs should be the goal, but certain asymmetries are inevitable (pausing, saving) or desirable (story-justified uniqueness). The real problems arise from effects that feel good to use on NPCs but terrible to receive — and from PVP/PVE skill splits that confuse players.

Key insight: Minimize the divide rather than trying to eliminate it entirely; replace binary disabling effects (paralysis, charm, knockout) with softer versions (slow, stun, attack penalties) that feel fair when applied to both players and NPCs.

Source: https://www.youtube.com/watch?v=goZlBF8Vsgs

The Core Question

Tim responds to a viewer question: in many RPGs the player seems governed by different rules than NPCs. NPCs have no abilities, seem shocked by common magic, are immune to traps, or aren't targeted by monster AOE. What design processes close this gap?

Tim notes upfront that not everyone even agrees this is a problem — some players actively enjoy the asymmetry, seeing traps and creatures as existing purely for their benefit.

Strive for One Ruleset

The first principle: try as hard as you can to make one set of rules that applies to both players and non-players (including creatures, not just humanoid NPCs).

Combat and Equipment

NPCs should be able to:

  • Cast spells and use items just like the player
  • Wear armor and wield weapons with the same bonuses
  • Pick up equipment from the environment — if an NPC picks up a fallen enemy's weapon and starts using it, that's "really cool and adds a lot of variety"

Dialogue

Dialogue is trickier because most dialogue skills involve influencing the NPC, which is inherently asymmetric. Tim suggests viewing rising skill check thresholds as the NPCs "getting better perception" — the system represents a two-way interaction even if mechanically it's one-sided.

Dialogue will "frequently be a special case" until fully generative dialogue exists.

Justified Player Uniqueness

It's "perfectly okay and reasonable" for the player to be special — if the setting explains why:

  • Pillars of Eternity: The player is a Watcher who can see and speak to the dead
  • The Outer Worlds: The player has brain damage that explains their ability to slow time in combat

Both abilities were limited in scope and grounded in lore, reinforcing why the player is central to the story: "You're our only hope, you're the only one who can do this."

Unavoidable Player-Only Abilities

Some asymmetries are simply inherent to being a player of a video game:

  • Pausing — NPCs can't freeze time to think
  • Saving and loading — The player can try something, reload, try again. NPCs can't. Tim mentions that during early Fallout development, they considered giving a boss NPC save/load abilities — "it was a tough sell"
  • Fast travel — Not a skill or spell, but functionally a player-only ability

The Fast Travel Design Cost

If you remove fast travel, you're committing to significant design work:

  • Quests must provide enough clues and landmarks to find locations naturally
  • Travel between locations must be interesting with things happening along the way
  • Otherwise "walking back and forth between towns and dungeons will get very boring very fast"

Things Players Hate (Realism vs. Fun)

Some realistic mechanics exist in the world but shouldn't apply to players because "realism isn't fun":

  • Permanent death — Players hate it in most contexts
  • Non-resurrectable NPCs — Tim recounts playing a cleric in Baldur's Gate with Raise Dead but being unable to resurrect a farmer's dead child. "I live in a world where resurrection exists and the ability is given to me and I can't do it."

In Arcanum, they did allow resurrecting quest NPCs — and it required enormous extra work tracking NPC death states and their effects on quest lines.

PVP vs. PVE Skill Splits

Tim strongly advises against having skills that work differently in PVP versus PVE:

  • PVP-only skills feel worthless to PVE players — "you just gave them something that fills up their player sheet that they will never use"
  • Skills that change behavior in PVP are confusing — "I played this game for years, then I go into PVP and it's like, what? These don't work?"
  • PVE is typically an order of magnitude more popular than PVP (often 10:1), so designing around PVP at PVE's expense serves the minority

The Asymmetry Players Actually Want

The hardest design problem: players love using certain effects on NPCs but hate having them used on themselves:

  • Knocking unconscious
  • Paralyzing
  • Charming (taking control)
  • Stealing items

Tim's Solutions: Softer Alternatives

Replace binary disabling effects with graduated ones that feel fair on both sides:

Hard Effect Soft Alternative
Knockout (unconscious) Stun with visible timer bar
Paralysis (complete stop) Slow (reduced speed and attack rate)
Charm (full control loss) Immunity shield (can't attack boss, but can buff/heal — redirects action rather than removing agency)
Stealing items No good solution found — Tim notes that even the iconic child pickpockets in Fallout 2's Den were hated by players

Boss Exception

Powerful bosses can reasonably share the player's resistance to hard effects. If a knockout ability only stuns a boss, players accept this — "they understand that sometimes bosses have that same division in the world that players do."

Tim's Recommendations

  1. Make one ruleset for players and NPCs, except for truly unavoidable player abilities (pausing, saving)
  2. Justify player uniqueness through setting and story — establish this before designing mechanics
  3. Avoid skills that work differently on players versus NPCs or in PVP versus PVE
  4. Replace disabling effects with softer versions (stun instead of knockout, slow instead of paralysis)
  5. Accept the divide can't be fully eliminated — minimizing it is a worthy goal, but some asymmetry is inherent to the medium

References