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.
Loading puzzle...
Preparing the game 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.
Official Rules
For the full original rules, examples, and advanced options, read Simon Tatham's official manual.
Read the official manualFrequently Asked Questions
More Logic Collection Games
Keen
Complete the latin square in accordance with the arithmetic clues.
Light Up
Place bulbs to light up all the squares.
Loopy
Draw a single closed loop, given clues about number of adjacent edges.
Magnets
Place magnets to satisfy the clues and avoid like poles touching.
Map
Colour the map so that adjacent regions are never the same colour.
Mines
Find all the mines without treading on any of them.
Mosaic
Fill in the grid given clues about number of nearby black squares.
Net
Rotate each tile to reassemble the network.