The core loop
Find the few actions a player repeats every few seconds, and the bigger loops that wrap around them.
Core loop
The small cycle of actions a player repeats most of the time they play. Its shape is almost always the same: act → get feedback → get a result → decide what next → act again. If this loop isn't fun on its own, no amount of levels, story or unlockable items will save the game.
Tetris: see the piece → move and rotate it → drop it → rows clear → next piece. One turn takes a few seconds.
DESCRIBE IT WITH VERBS
A game is what the player does
The quickest way to see a core loop is to list its verbs: the actions the player actually performs. Jump, shoot, place, match, build, trade. Not "a game about a plumber" but "run and jump". Super Mario Bros.' core verbs are exactly those two, and nearly everything in its levels exists to make running and jumping interesting.
A useful test: can you describe the core loop in one sentence with three to five verbs? If you can't, the design is probably still unclear, even to its designer.
Check yourself
Match each game to its core verbs
Show the answer
- Tetris → Rotate, drop
- Minecraft → Gather, craft, build
- Super Mario Bros. → Run, jump
- Stardew Valley → Plant, water, harvest, sell
One day in Stardew Valley (2016)
plant seeds
↓
water them
↓
harvest the crops
↓
sell them
↓
buy more (or better) seeds
↓
plant againSeeds turn into crops, crops into money,
money into more seeds. The loop grows.Many loops work like a small economy: they turn one resource into another and back. Minecraft does it too: explore → gather → craft better tools → build or survive → explore further.
Check yourself
Which is the right order for a day in Stardew Valley's core loop?
- Sell → plant → harvest → water → buy seeds
- Plant → water → harvest → sell → buy seeds
- Buy seeds → harvest → plant → sell → water
- Water → sell → plant → buy seeds → harvest
Show the answer
Plant → water → harvest → sell → buy seeds
Yes. Each step produces what the next one needs: planted seeds need water, grown crops can be harvested, crops become money, money becomes seeds.
LOOPS INSIDE LOOPS
Seconds, minutes, weeks
Most games stack loops of different sizes:
- Moment to moment (seconds): a single jump, a single dropped piece.
- Session (minutes): finishing a level, getting through one in-game day.
- Long term (days or weeks): unlocking new worlds, growing a farm, levelling up a character.
Each outer loop gives you a reason to keep doing the inner one. You jump because you want to finish the level; you finish levels because you want to see the next world.
In a platformer: jumping a gap is the inner loop, clearing the level is the middle one, and unlocking a new world is the outer one.
Like the hands of a clock
The second hand goes round sixty times for every lap of the minute hand, and the minute hand goes round many times for each lap of the hour hand. Game loops are nested the same way: many jumps per level, many levels per world. Where the analogy breaks: a clock's hands turn at a fixed rate, while a player chooses when to push the bigger loops forward.
Check yourself
A platformer: sort each activity by the size of its loop
- Run and jump over a gap
- Stomp an enemy
- Reach the flag at the end of a level
- Beat the boss at the end of a castle
- Unlock a new world on the map
- Collect every star in the whole game
Show the answer
Moment to moment (seconds): Run and jump over a gap, Stomp an enemy
Session (minutes): Reach the flag at the end of a level, Beat the boss at the end of a castle
Long term (days, weeks): Unlock a new world on the map, Collect every star in the whole game
Check yourself
Arash's team made a platformer with beautiful worlds and a big unlockable map. Testers say jumping feels stiff and they stop after ten minutes. What should the team fix first?
- Add more worlds so there's more to unlock
- Add a reward screen after every level
- The jump itself: the moment-to-moment core loop
- Make the map even more detailed
Show the answer
The jump itself: the moment-to-moment core loop
Right. The inner loop is what players do every few seconds. If jumping feels bad, every world and reward just asks them to do more of something they don't enjoy.
Find the core loop of any game
- Watch what the player does most of the time, not what the trailer shows.
- Write the actions as 3-5 verbs in a circle: act, feedback, result, decide, act.
- Ask what the next bigger loop is: why does the player keep repeating the small one?
- Check whether the small loop would still be fun with no rewards at all.
Check yourself
Great unlockables and rewards can make up for a dull core loop.
Show the answer
False
False. Rewards are outer loops; they only give a reason to keep doing the inner one. A common mistake is designing skins and levels before the second-to-second action feels good. Build the small loop first.
Lesson recap
- The core loop is the small cycle a player repeats most of the time: act, feedback, result, decide, act.
- Describe a game by its verbs. Super Mario Bros.: run, jump. Tetris: rotate, drop.
- Loops nest: seconds (a jump), minutes (a level), weeks (unlocks). Each outer loop is a reason to repeat the inner one.
- Economy loops turn one resource into another; when they grow the player's power, the challenge has to grow too.
- If the small loop isn't fun, the big ones can't save it. Fix it first.
- Notebook: draw your favourite game's core loop as a circle of 3-5 arrows.