Inertia Puzzle Online

Inertia is one of the classic one-player logic games in Simon Tatham's Portable Puzzle Collection. Collect all the gems without running into any of the mines.

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Preparing the board and controls.

Game Objective

Collect every gem without hitting a mine. The ball does not move one square at a time: after you choose a direction, it keeps sliding until it hits a wall or lands on a stop square marked with a broken circle.

Collect all the gems without running into any of the mines.

How to Play

Choose one of the eight directions with the numeric keypad, direction controls, or by clicking on the grid in the direction you want the ball to travel.
Clicking a far square chooses a direction; it does not mean the ball will stop there.
These puzzles reward careful deduction more than speed. Start with the most constrained clues, eliminate impossible choices step by step, and avoid guessing unless the puzzle specifically calls for it.

Beginner Tips

Before moving, trace the whole slide path and identify the exact square where the ball will stop.
You collect gems by sliding over them, but touching a mine at any point on the path is dangerous.
Use stop squares as safe parking places. A good move leaves you stopped somewhere with another safe route.