What is a loop in game design? How does a strong engagement loop contribute to a game’s success?

The loop is one of the most fundamental concepts in video game design. Identifying your game’s loops helps you keep your design focused, by clarifying what makes your game compelling (or the reverse) and allowing you to direct your work towards strengthening those features.

What is a Loop?

Let’s start by defining the simplest loop – a repeating cycle of two steps:

• Action: The player performs an action. (e.g. presses a button on a controller).
• Feedback: The player receives feedback that their action has taken place (e.g. their character performs a jump on the screen).

By itself, this isn’t particularly useful for designing a good game. What’s it missing? A reason for the player to perform the action.

In games, the player is usually motivated by the desire to proceed towards a goal – either one provided by the game (rescue the princess in Mario) or one they’ve defined themselves (build a working computer in Minecraft). So let’s add a bit more to our loop definition:

• Motivation: The player wants to achieve a defined goal.
• Call to Action: The game provides a means to progress towards the goal.
• Action: The player performs an action.
• Feedback: The player receives feedback that their action has taken place and they have made progress towards their goal.

The feeling of making progress is satisfying. It’s a reward. It feeds back into the player’s motivation, keeping them in the loop. By strengthening that feeling of reward, we can strengthen the player’s motivation and increase our chances of keeping them engaged.

Most games have multiple loops, operating on various levels and timescales – shorter-term and longer-term goals. Loops can be nested, with bigger loops made up of many small loops. They can lead into one another, with the player’s goal changing as each loop is completed.

Some examples of loops that can motivate players:

• Matching gems on a board to earn points. (goal: get enough points to win the level.)
• Killing monsters to collect in-game currency. (goal: get enough money to buy an item.)
• Collecting in-game currency and buying items with it. (goal: max out your character’s power level.)
• Completing quests. (goal: get to the next bit of story/collect a nice reward.)
• Running, jumping and dying. (goal: improve your skill and progress further on the next run.)

(“Achievements” are an interesting case where the goal is extrinsic, earned outside the game, rather than intrinsic to the game. They can be useful additional motivators, but are no substitute for good gameplay.)The Core Loop

Perhaps the most important loop to think about is a game’s core loop. This is the base action or series of actions that are repeated over and over throughout a game. It’s the lowest level loop – the one that really defines what players do in your game. If the core loop isn’t fun and rewarding in itself, you’ve got your work cut out to win over your players.

Some examples of core loops:

• Don’t Starve: Exploring and collecting crafting ingredients.
• Gems of War: Matching 3 or more gems on a board.
• Hollow Knight: Walking, jumping and attacking.

So how do you make these core loops rewarding? You address each step of the loop:

• Motivation: Provide short-term and long-term goals to drive player motivation.
• Call to Action: Make sure it’s clear that engaging in the core loop causes progress towards the goal.
• Action: Provide agency – a choice of possible actions at a given moment.
• Feedback: Add juice – visual, audio and tactile effects that make the action feel satisfying.

A great way to keep a game interesting while retaining a focused design is to look for ways to embellish and vary the core loop. Add depth, challenge, and unpredictability. Make the challenges harder, and the rules more complex, as the player’s skill increases. Make them feel like they are succeeding, and reward them for being smart.Engagement Loops

Another type of loop to pay attention to is the engagement loop. The concept of engagement came to prominence with the advent of free-to-play games, which measure success by the “conversion” rate of players buying premium currency for real money. The more players engage – logging in more regularly and playing longer sessions – the more likely they are to put money into the game.

So how do you keep players engaged? You make sure they feel rewarded for logging in:

• Motivation: The player wants to make progress in the game.
• Call to Action: The game may inform the player that they can make progress – e.g. with a notification that a timer has finished.
• Action: The player logs into the game (engagement).
• Feedback: The player is rewarded for logging in (e.g. by collecting accumulated resources and daily login rewards).

In addition to rewarding players, it’s important to minimise barriers to player engagement. If your game takes an age to load, has poor frame rate, or makes the player click several buttons to perform a simple common action, they are much more likely to give up on it.

There’s a lot more that could be said about loops, reward and engagement in game design, but I hope by covering the basics here I’ve given you the confidence to use these concepts in your own designs. Always remember that throwing extra features at a mediocre game rarely makes it any more fun: instead, look at how you can improve the loops – core and otherwise – to create a compelling experience.