Lodestone

Drop charges around a field maze and shape the force landscape so a launched particle arcs cleanly to the goal.

How to play

Each level has a test particle, a goal, and walls. You place point charges to sculpt the field, then launch the particle and watch it accelerate under real Coulomb attraction and repulsion. On magnetic levels a uniform field curves the trajectory into arcs.

• Choose a positive or negative charge with the sign selector.
• Click in the field to place charges where they'll steer the particle.
• Press Launch to release the test particle and watch it respond to the forces.
• Thread the particle through the gaps to the goal to clear the level.

Controls

• Desktop: pick + or - charge, click the field to place charges, click Launch; switch Daily/Practice in the bar.
• Phone & tablet: tap to set the sign and tap the field to place charges — fully touch-friendly.

Tips & strategy

• Opposite charges pull and like charges push — place a charge past the goal to draw the particle in, or behind a wall to deflect it.
• Charge force falls off sharply with distance, so a charge nudged closer has an outsized effect.
• On magnetic levels, plan for a circular arc rather than a straight shot and set up the radius that threads the gap.

What you'll learn

Lodestone is a hands-on electromagnetism sandbox where the puzzle is engineering a field rather than aiming a shot.

• Skills: electromagnetism, fields, physics, engineering
• Best for: roughly grades 10–12 (ages 15+)
• For parents & teachers: engineering electromagnetic fields.

About Lodestone

Lodestone is a hands-on electromagnetism sandbox where the puzzle is engineering a field rather than aiming a shot. It's an original, free browser game integrating genuine Coulomb and Lorentz physics, with daily and practice runs.

A free, original browser game on PlayPendium — no download, no install. Browse all games →