Summary

An interaction loop is the repeatable cycle through which a player learns, tests, and refines a skill. Students usually meet this idea through questions like “how do players learn mechanics?”, “how do I teach without a tutorial pop-up?”, or “why does a mechanic stop engaging people?” The LDARF model (Learn → Decide → Action → Rules → Feedback) answers those questions by breaking every mechanic into a visible learning cycle, while skill chains show how simple loops connect into more advanced mastery. (CRE342 Lectures, see source-cre342-lectures)

For the broader theory behind why skill acquisition is pleasurable, see fun-as-learning.

Key ideas

The player model

The player is an entity driven — consciously or subconsciously — to learn new skills of high perceived value. They gain pleasure from successfully acquiring those skills. (see fun-as-learning, neurochemical-engagement)

This model has two critical components:

  • Driven to learn: Play is instinctual. In the absence of more pressing demands, people begin playing by default. Boredom and frustration are feedback mechanisms that prod players toward more stimulating challenges.
  • Perceived value: The perception of a skill’s value matters more than its objective value. Players will invest enormous effort into skills they believe will help them progress — and rapidly abandon skills that feel pointless.

The LDARF interaction loop

A game interaction loop describes the repetitive sequence through which a player learns and uses a specific skill. The five components:

StageDescription
LearnPlayer encounters something new — a mechanic, enemy, obstacle. They begin building a mental model.
DecidePlayer evaluates options: What can I do here? What’s the cost? What’s the benefit? What alternatives exist?
ActionPlayer executes an input — button press, movement, placement, spoken choice.
RulesThe game’s systems process the action. These rules are initially a black box — unknown to the player, but learnable through repetition.
FeedbackThe game responds. This response updates the player’s mental model and feeds back into the Learn stage.

The loop then repeats, each iteration refining the player’s understanding until mastery is achieved — what Koster calls grokking: understanding a causal link with certainty and being able to repeatedly cause the desired effect (see fun-as-learning).

Learning through cause and effect:

  • Association — “When I do something, something happens” (fuzzy)
  • Sampling — The more they practise, the more certain they become
  • Grokking — They understand the causal link with certainty and can exploit it reliably

Skill chains

Individual interaction loops are not isolated — they form a directed graph called a skill chain. Simpler skills must be mastered before higher-complexity skills become accessible. Mastery flows down the chain.

[Jump] → [Double Jump] → [Wall Jump] → [Air Dash]
                 ↓
          [Jump Attack] → [Aerial Combo]

Case study: Zelda: Breath of the Wild skill chain atoms:

  • Basic Movement: Walking → Running → Jumping
  • Exploration: Climbing → Swimming → Gliding
  • Puzzle Solving: Magnesis → Cryonis → Remote Bombs
  • Combat: Basic Attack → Advanced Attack → Dodge/Block
  • Crafting: Collecting Materials → Cooking → Making Potions

Feedback loops within the chain:

  • Positive: Successfully defeating enemies with advanced combat rewards better loot, incentivising further skill development
  • Negative: Failing a shrine puzzle resets it, encouraging the player to reconsider their approach

Skill status

Every skill atom in the chain has a status reflecting the player’s current relationship to it:

StatusDescription
UnexercisedThe player has not yet attempted this skill
ActiveThe player is practising — building mastery (can become a grind)
Partially MasteredThe player has some command but not fluency
MasteredThe player has achieved reliable, fluent use
Burned OutThe player mastered it but has lost interest in using it

Mastery must flow from foundational atoms. If a player is blocked early in the chain, they will never reach the further atoms — even if those atoms are well-designed.


Skill failure — diagnostic model

When players fail to learn a skill, the failure can be traced to a specific point in the LDARF loop:

Loop stageFailure modeCommon causes
LearnPlayer didn’t build the right mental modelIncomplete prerequisite skills; insufficient learning time; wrong schema
DecidePlayer chose not to engagePerceived cost too high; perceived benefit too low; better alternatives existed
ActionPlayer couldn’t executePhysical difficulty; controls unclear; required technique not yet taught
RulesCausal link wasn’t learnableRules too dynamic (no consistent pattern); too complex to convert to cause/effect
FeedbackPlayer didn’t receive or process feedbackNo feedback present; feedback ignored; multiple competing stimuli masked it
BurnoutPlayer mastered but disengagedSkill no longer provides novelty or perceived value

Critical insight: Learning failures are almost always design failures, not player failures. If the majority of players cannot learn a skill, the problem is in the architecture — the prerequisite chain, the feedback, or the perceived value — not in the players.


Skill trees

A skill tree is the UI manifestation of a skill chain — a graphical representation of the progression of skills, abilities, or upgrades that a player can unlock. It makes the otherwise implicit directed graph visible and navigable.

Functions:

  • Customisation — players choose paths aligned to their playstyle, making each run unique
  • Progression signal — unlocking nodes provides explicit acknowledgement of advancement
  • Strategic depth — choices about which path to pursue create meaningful decisions
  • Replayability — different build paths encourage multiple playthroughs

Player types and motivation

The CRE133 lectures reference several player type taxonomies relevant to skill motivation:

  • Bartle’s Taxonomy (Achievers, Explorers, Socialisers, Killers)
  • Yee’s Gamer Motivation Model
  • Lazzaro’s Four Keys to Fun
  • Self-Determination Theory applied to gaming (see self-determination-theory)

Different player types will value different kinds of skill mastery — a competitive player prizes combat skill chains; an explorer prizes navigation and discovery chains.