Game Loop Fundamentals

What is a Game Loop?

Each game has a series of small actions that are consistently repeated. This is why it is considered a loop.

The game loop is broken down into five time-based goals:

Per second goals - immediate actions
Per minute goals - short-term objectives
15 minute goals - medium-term tasks
Hour goals - significant milestones
Long term goals - ultimate objectives

Establishing Your Game Loop

Establishing your game loop is one of the first experiences you should create. A proper game loop can be created in a prototype, demo, or vertical slice. It shows the full circle experience of what you’re trying to portray through a game.

Proof of Concept Timeline

A game loop can be proven in as little as ten minutes of gameplay. In fact, when pitching a game to a publisher, you shouldn’t aim for much more than a ten minute experience to prove your game idea is interesting.

Most of the time your team is using:

Temporary low quality art and quick coding techniques
Marketplace assets and Mixamo to achieve a vision
Rough art assets that you or your team has created

Development Philosophy

Pre-Production Focus

Gameplay code won’t be optimized and is frequently built in a messy manner. This is part of the pre-production process in game design - research and development.

Clean Rebuild

When research and development is complete, projects are recreated from scratch with a more organized and clean coded construction.

Since the goal is to prove if a game concept is working or not, speedy development process is prioritized over a clean and well-setup project.

Development Progression

Once the core game loop is finalized, the project will be given the go ahead for the next stage. This can sometimes be:

Full development
Advancing the project from a ten minute session to a 60 minute experience that is re-evaluated at that time

Documentation Through Development

Each time the game passes these stages, it’s important to document what it looks and feels like through:

Gameplay recordings
Saved packaged builds

These are called pre-vis or pre-visualizations - they can be a great visual representation and reminders on the game’s development journey.

Scope Creep Dangers

Scope creep can lead to:

Much longer development cycle than originally planned
Can cause the game to lose its core experience that was originally found as fun

Maintaining Core Focus

If you’re building a game around combat - proving the combat feel is the goal. This could be a short experience defeating enemies with small adventures towards a final boss encounter.

If you’re building a crafting game - proving that gathering resources to design a beautiful home is a fun experience.

Per Second Goals

Per Second Goals are when the player is constantly thinking about what to do next.

Examples by Game Type

Per second goals are largely around managing your stealth. Every second, you’re looking for coverage to not be detected.

Combat-Focused Per Second Analysis

In combat scenarios, players constantly assess:

Your enemies and what they are doing - where they are, are they attacking you or an ally?
Best ability rotation to maximize combat performance
Which actions are on cooldown and which ones are almost off cooldown?
Position requirements such as a backstab
Health and resources to make decisions to drink health potions, dodge an attack, or start running away

Per Minute Goals

Every time we take a step back to the next level of time-based goals, it will lead to the theme of driving player motivation. In this case, per second goals are often driven by a player’s motivation towards per minute goals.

Examples by Game Type

Stealth/Survival

Focus on identifying objects or threats. Every minute the player will begin looking for supplies, health, ammo, collectibles, enemies to avoid.

Platformers

Typically involve picking up collectibles, like coins, stars, or moons in order to progress the game or increase your score.

Capture the Flag

Evaluate where each flag is on the map. Every minute you are looking at the map to understand where your flag is located and where the enemy flag is located.

Action Combat

Evaluate your current surroundings for additional threats. Every minute you are looking for the next enemy to fight in the surrounding area.

Crafting and Story Examples

Crafting games: Per minute goals would be tracking your progression on the current recipe you were trying to build. Every minute you’re checking if you have all the ingredients you need to craft your item.

Story games: Per minute goals would be completing the puzzles or thinking about the clues and secrets you discover. Every minute, the player is evaluating what you have uncovered and trying to think of the story as a whole.

15 Minute Goals

Fifteen minute goals begin to take a much bigger step back in the overview of a game loop.

Quest and Mission Framework

For many game genres, this is where quests, missions, and general objectives come into play. From the objective user experience lesson, we reviewed what many of these goals could be:

Defeat or kill quests, loot, escort spawn and follow
Escort walk to and defend, delivery, explore, defend
Interact, craft, and gather
Unique game specific objectives will always be something to consider for design

Level-Based Goals

You can also plan 15 minute goals based on each level. You could break down your levels into 15 minute experiences. A 15 minute goal is to finish a level.

Flexible Timing

As a reminder, 15 minutes is a general guideline. They could be 10 minute or 20 minute levels to suit the needs of your design.

Character Progression

The next segment for 15 minute goals is short term character progression. This could be something small like:

Upgrading a weapon or a piece of armor
Getting experience to increase their character’s level
Upgrading single skills and abilities to become stronger

For character progression, 15 minute goals are typical smaller increases in power or advancement.

Game-Specific Examples

The goal here could be to win the match, to capture the most flags in a 15 or 20 minute match.

Hour Goals

Hour-based goals now take a huge step back in the grand scheme of a game loop.

Flexible Duration

Just like 15 minute-based goals, the range of time can vary dramatically at this stage. After all, some games might only be a few hours long. It can be changed based on the game design needs, so it could be closer to 30 or 90 minute goals.

Major Progression Examples

Hour-based goals represent significant milestones:

Quest Chains

Completing a quest chain - a series of quests that have a specific order that ends with a large reward to the player, or finishing all the quests and objectives in an area which forces the player to explore the next town or region.

World Progression

From a platformer perspective, this could be gathering all the collectibles in a level, which unlocks a new world to explore.

Character Power

For character progression, it could be reaching a much higher power level to unlock stronger abilities and skill points. Maybe the character’s level is high enough to explore a new dungeon.

Equipment Sets

For crafting, it could be to obtain a set of equipment - a full set of copper tools, or upgrading to almighty silver tools.

Story and PvP Progression

Story games: It could be much bigger story beats and progression - moments that are plot twists or critical choices for a player that change the direction of the game.

Capture the flag: It could be account progression such as a battle pass, experience, or more loadout options. Anything player versus player or combat can also have skill depth and progression as an hour-based goal.

Skill Development

Is the player becoming more skilled at the game?

Long Term Goals

Long term goals are a guiding light for the player to keep playing.

Completion Variations

For many games, this will be straight out finishing the game, but in today’s day, finishing a game can have multiple meanings depending on the player:

Some will just want to beat the final boss and roll the credits.

Skill-Based Long Term Goals

Player versus player and competitive titles - improving player skill can be a never ending journey. Think about speedrunners as they theorycraft new ways to play or glitch a game in their efforts for a world record.

Creative games - the long term goal is to create cool stuff. From cozy cottages to giant skyscrapers to expansive castles, creative genres can simply go on forever.

Player-Driven Experiences

During our accessibility lesson, game difficulty is becoming a player-driven gameplay experience, with game modes like Hardcore, Ironman, and Solo Self-found.

Online MMORPGs have the long-term goal of:

Getting to the max level
Leveling trade skills, farming for more gold
Experiencing challenging raid content with a group of friends

Epic Goals

Long-term goals can be very game-specific, but they should always entice the player to keep playing:

Acquire the best weapons and loot
Reveal the full story and see the best cinematic cutscenes
Becoming the best player on a leaderboard
Building beautiful creative experiences

Creating a solid game loop can take time, but it’s important to break it down into small experiences you can design that add up to a bigger picture. The game loop provides structure and motivation that keeps players engaged from moment to moment all the way through to completion.