Big Walk 100 completion goes beyond reaching the normal ending. The PlayStation trophy list separates “Finish the game” from “Completely finish the game,” and the second requirement is attached to the Big Game trophy.
Finish the handcrafted main route first
The official FAQ describes Big Walk as a start-to-finish cooperative adventure with a beginning, middle, and end. Keep the same host for continued sessions because the host owns the save, starts the world first, and is required when the group returns to that progress.
Complete the tower progression and the normal ending before treating every unexplored structure as a completion blocker. This keeps the main route distinct from optional cleanup and makes the late-game map state easier to interpret.
Complete the purple-puzzle route
Completion reports consistently identify a late-game purple area containing harder additional puzzles. Their purple rewards are still progression objects, but they belong to the post-main-route cleanup rather than the opening tower path.
Community walkthrough documentation records seven purple rewards and a final collection structure near the map-room area that also accepts unused ordinary rewards. Because these details reveal endgame structure, groups avoiding spoilers should stop after confirming that the purple area is their next incomplete region.
Confirm the final completion state
Use the host's saved world and check that every remaining reward intended for the final collection structure has been deposited. The trophy list provides the objective confirmation: Big Game is awarded for completely finishing the game, while Big Trophy is the separate platinum requirement for unlocking every other PlayStation trophy.
Do not use the trophy count alone as a puzzle checklist. Several trophies are traversal or equipment milestones, including visiting the map, riding the chairlift and train, wearing storage items, reaching the highest point, and getting shiny.