What it is. A field the player projects from a point — attract draws magnetic bodies toward it, repel shoves them away. You never touch the object; the force does. It’s mechanic-throw without the hands: action over a distance, on anything the world marks as magnetic.

Player fantasy / why it’s fun. You bend the room with an invisible hand. Coins leap to your palm, a portcullis rips off its track, a mob of foes clumps then scatters at your whim. The pull is telekinesis with rules — power you feel through second-order motion, not a button that just deletes the obstacle.

The verb

Aim a point (or emit from self) → choose polarity (attract / repel) → hold → magnetic bodies accelerate along the field until you release or they arrive. Two live decisions every frame: which polarity and what’s in range.

How it feels / why it’s fun

• Second-order control. You don’t move the object; you move the force, and the object obeys physics. The delight is the lag — you lead, it follows, it overshoots. That gap is the skill, same family as the arc-read in mechanic-throw and anchor-peggle.
• Polarity is a live toggle, not a mode. Flipping attract↔repel mid-motion is the expressive core: yank a crate close, then shove it through a wall of foes. One input, two verbs — keep the flip instant and readable.
• Crowd authoring. Against many bodies the field is a brush. Repel is peel-off crowd control (system-combat-model); attract is a trap primer — gather, then detonate. See genre-horde-survival.

Tuning levers

Defaults target physics-puzzle feel: legible, mid-range, instant flip. Widen range and flatten falloff for arcade crowd-control; add a battery and inverse-square for a tense management verb — system-resource-loops.

Self-vs-object: who moves?

The single biggest design fork.

• Object-attract (you anchored). The world comes to you. Reads as telekinesis; native to puzzles and tower-style crowd control. Weight the player heavy so recoil doesn’t drag them.
• Self-attract (you’re the metal). Fire the field at a fixed anchor and you fly to it — now it’s a traversal verb, cousin to mechanic-grapple and mechanic-teleport. The room’s magnetic points become a movement graph; this is the genre-metroidvania seam.
• Both, toggled is richest and heaviest to teach. Gate it: teach object-pull first, introduce self-pull as a named traversal beat — system-onboarding, pattern-mastery-and-flow.

Legibility: mark what is magnetic

The whole verb collapses if the player can’t tell what the field grips. This is the non-negotiable:

• One loud material cue. Magnetic bodies share a single unmistakable read — a color, a shimmer, a metal sheen. Everything else is inert scenery. Don’t make the player probe to learn the ruleset — pattern-readability, system-telegraphs.
• Show the field. Range ring, polarity color (warm=pull, cool=push is a safe convention), and force lines so the player predicts before committing. A field you can’t see is a coin flip.
• Poles must be unambiguous. Attract and repel need distinct color and shape language — color-blind-safe, an system-accessibility gate, not a nicety.

One field, many uses

A magnet is a verb multiplier — the same force is a key, a weapon, and a floor:

• Key: pull a lever, rip a barred gate, drag a metal bridge into place.
• Weapon: repel foes into system-hazards-and-environment; attract a spiked crate into a crowd.
• Traversal: self-pull across a gap between anchors. One authored room yields three challenges depending on which use it demands. Design each room to be interesting under at least two of them — that constraint is where the pattern-emergence lives.

Slots into

• Genres: genre-physics-arcade (native soil), genre-grid-puzzle and genre-puzzle-platformer (discrete, provable field moves), genre-horde-survival and genre-bullet-hell (crowd shove / bullet-bend), genre-metroidvania (self-pull as a gated power), genre-immersive-sim (a physics verb that composes off-script).
• Anchors: anchor-portal (a physics tool that reframes each room), anchor-katamari (attract-and-accrete as the whole loop), anchor-vampire-survivors (a repel/pull field as crowd control), anchor-nuclear-throne (magnetic ammo/health pickup as a quality-of-life field).
• Systems: system-hazards-and-environment (throw foes into the room), system-combat-model, system-status-effects (a “magnetized” tag), system-resource-loops (a metered field).

Twist seams

• Magnet but you are the metal and the world pulls you (perspective) — flip the frame: the player is ferrous and every anchor in the level exerts pull on them. Now you plan routes by which magnets are live, thread between competing fields, and get dragged into hazards you failed to read. Traversal becomes a field-navigation puzzle — pairs with mechanic-grapple, genre-metroidvania, and the “you are the exception to the world’s rule” energy of mechanic-gravity-flip.
• Magnet but same-polarity enemies clump then explode (emergence) — give foes a polarity. Attract like-poles and they resist, pile, and detonate at a density threshold; opposite poles snap together into a bigger, meaner mass. Crowd control becomes chemistry — you’re arranging reactions, not just shoving. See pattern-emergence, system-enemy-archetypes, genre-horde-survival.
• Magnet but polarity is the level’s, not yours (inversion) — the room decides the field; you only choose where you stand. Zones pull or push on a timer, and the puzzle is positioning inside forces you don’t own — system-hazards-and-environment, pattern-pacing-and-tension.

How it wires to Hayao

• Model the field as a per-frame force applied to magnetic bodies before the physics integrates: accel = polarity · strength · falloff(distance). The body’s motion is the solver’s job over fixed ticks — deterministic, replayable, hashable.
• Any tie-break when multiple fields or many bodies contend (equal distance, spawn order of a clump) resolves through ordered iteration or a deterministic RNG — never argless timing, or replays diverge and physics proofs break.
• For the pull/push/impact feel, study the physics lab in sandboxes/ in isolation before wiring it into a game.
• If the magnet is a puzzle move (grid, provable), keep it a pure Move — a field pulse that maps input state to a new cell layout — and split logic from view the way examples/sokoban/ splits pushable-object rules from rendering. The landing cell is state; the force lines you draw are cosmetic.
• The range ring, polarity glow, force lines, and metal-sheen cue are all cosmetic overlays — they read but stay out of world.hash(). What’s magnetic and where it ends up is state.
• Prove the field feel against design/FUN.md#19-·-physics-arcade; prove puzzle levels the way a puzzle proves winnability — every solution must have a reachable pull.

Fails when…

• What’s magnetic is invisible. If the player can’t tell metal from scenery, every attempt is a probe, not a plan — that’s antipattern-input-lie. One loud material cue, always.
• The field just deletes the obstacle. A pull with no lag, no overshoot, no cost is a teleport wearing a costume — the second-order skill evaporates into antipattern-false-depth. Keep the motion physical.
• Range trivializes routing. Room-wide, flat-falloff attract means you never approach anything — the level’s geometry goes dead and the optimal play is stand-and-hold: antipattern-boring-optimal.
• Poles read the same. Attract and repel that differ only by a hue nobody can parse under pressure is a readability and accessibility failure — distinct color and shape, or don’t ship it.
• The magnet is strictly the best verb. If pulling beats moving, meleeing, and shooting everywhere, the rest of the kit rots — antipattern-boring-optimal. Gate it: limit what’s ferrous, meter the field, or cost the polarity flip.
• Overloaded input. Attract and repel and dash on one button muddies the mental model — antipattern-feature-soup. Keep the field its own clean verb.

See also

• mechanic-throw · mechanic-grapple · mechanic-bounce — the other action-at-a-distance and physics verbs a magnet sits beside.
• mechanic-teleport · mechanic-gravity-flip · mechanic-portal — the “reframe the room with one force” family.
• genre-physics-arcade · genre-horde-survival · pattern-emergence · pattern-readability — the design frame this lives inside.