Vertical slice checklist for an indie game

A vertical slice is a small part of your game finished to a representative quality bar. Use it to test whether the experience works and whether you can produce more of it. Choose one player journey, then resist adding a second before the first is complete.

Choose the experience you need to prove

Write the player action, intended feeling and biggest uncertainty. Pick a path that includes the core loop and a meaningful outcome. A collection of disconnected mechanics cannot show whether the whole experience holds together.

Name one target player and one session goal.
Choose one start-to-finish path, including failure and retry.
List three assumptions the slice must test.
Write down what is deliberately outside the slice.

Make the path representative

Use enough final-quality work to expose production risks. Everything does not need polish: focus on the interactions that determine whether the game is readable, enjoyable and feasible to build.

The core action has readable input, visual and audio feedback.
Menus, instructions, pause, failure and restart support the entire path.
One environment and one important content item pass your intended quality checklist.
The packaged build runs outside the editor on a target configuration.
Record time spent and rework on the representative content item.

Observe players and decide

Ask players to attempt the goal, then watch without coaching. Record what happened before collecting suggestions. Separate a player’s observed difficulty from their proposed solution.

Can the player describe the goal after the opening?
Where do they hesitate, repeat an action or lose progress?
Which interaction produces the intended feeling?
Can your measured content workflow support the remaining scope?
Decide keep, change or cut for each risky assumption.

Turn the plan into a roadmap

Use the free roadmap template to connect phases, milestones and tasks. You can keep the spreadsheet or create a new GameInDev project with its 42 starter tasks.

Get the roadmap template →