The grapple

Hook, hold, let go

• Hook. The trigger fires the hook, a three-clawed grapnel on a cable, along your aim. It bites anything built or floating within 56 m: buildings, spires, drifters and their huts, and the Heart. Grass, trees and bunnies don't hold it. A miss costs nothing: the hook reels straight back.
• Hold. The reel pulls you toward the hook, adding 60 m/s² up to 28 m/s, almost three times the ground's pull. While the line is taut, gravity can't sag you off it: you ride the line you see, so a clear line means a clear flight. Speed you already had, from running or flying, stays with you.
• Over the edge, never into the wall. On an edge, the reel aims 3 m above the hook, so the line, and you on it, pass over the edge. Aim at the top third of a wall and the hook climbs to its edge for you; on a spire it climbs to the deck.
• Edges fling. Once your feet clear the edge, the line lets go and flings you on with nine-tenths of your speed plus 0.3 m/s for every metre of line you hooked from (9 m/s from 29 m), the way you look, never lower than level. Hook from far and look up for a big throw; hook from close for a hop. Stopping on the roof is the exception: look down as you go over.
• Let go. Any time, and you keep your speed. Let go partway up a long pull and you sail on along it; that is how a spire throws you across the world.
• Wells. On a drifter or the Heart, the line stops 3 m off the surface and holds like a rope. Your speed carries you round, the reel and the well both pull inward, and each turn gets faster. Let go when you face where you want to go.
• Two hooks. Two charges, each back after 3 s, with a lamp on the gun's flank for each. Crossing a gate cuts the line.

The reach scales with the world: 56 m is 0.575 of the radius. That is just enough to reach the Heart from any spire deck, 53 m away at 0.65× and 84 m of 86 at 1×, so the Heart becomes a roundabout where a crossing can change direction.

What other games found

• Titanfall 2. Its grapple pulls fast and lifts you, but adds little speed; a homemade copy that added more became hard to control (three.js forum). Respawn wanted skilled players to wrap the rope round posts to turn (GamingBolt). Here the reel tops out at 28 m/s, and the extra speed comes from turning round a well.
• Overwatch's Wrecking Ball. The claw's anchor becomes a pendulum to build speed from, and it can't attach to anything that moves or breaks (Overwatch Wiki). Wells work like that here, and only things that stay put hold the hook.
• Batman: Arkham. The grapple boost flings Batman off the ledge he pulled to, and the city is crossed without touching the ground (PlayStation Blog). The fling at an edge is that move, with your look choosing the throw.
• Sekiro. A grapple point in range pulls you straight onto the building or branch above it, and some points launch you forward the way you face (Twinfinite, Siliconera). Designed grapples carry you over the edge rather than into the wall below it, and this one does the same.
• Halo Infinite. The grappleshot made its team rethink levels, since walls and gaps stopped being barriers (NME), and a miss doesn't start its cooldown (Halopedia).
• Apex Legends. Pathfinder's grapple cooldown grows with how far he travels (Apex Legends Wiki). Charges are simpler to read, so they come first.
• Marvel's Spider-Man. The team narrowed the roads and added an outward push so swings stay centred (Popular Science). The city is tuned for the swing, and the towns below are tuned for the grapple the same way.
• Super Mario Galaxy. A nearby planet's pull can capture a jump (Super Mario Wiki). A drifter does that to a flying bunny.

Reading it

• Before you fire. A mint ring marks where the hook would bite, on the roof edge if it is going to climb, and nothing shows when nothing in reach would hold it. The reticle can add the distance later.
• While you hold. Near an edge, dots show where the fling will throw you for the way you are looking, so you aim the throw with your eyes. Away from edges, the fall arc that already shows in the air shows where you would land if you let go now.
• The line is the path. While it is taut you travel along it, so where it goes, you go. A black cable with the gun's mint rim, the hook's claws open at its end. The reel whirs higher the faster you go and zips the hook home when you let go.

The gun

A grapple gun in the rifle's black metal and mint rim, shaped like a speargun. A long barrel carries the hook in its mouth, three chunky claws folded back along it. The reel hangs under the barrel where the rifle's magazine would be, a spool of cable between two holed flanges, so you see it spin. The receiver has a ring sight and two amber lamps down its flank, one for each hook ready, and the rifle's swept grip. The right paw holds the grip and the left the foregrip.

Firing kicks the gun and spins the reel out; the hook flies with its claws open and bites with a clank. Letting go zips it home, and it slides back into the mouth with a click. Like every gun now, its bore runs parallel to your view, so it points at the reticle.

It is weapon 3: the 3 key, and the wheel steps through all three.

Towns as anchors

The grapple needs things to hold. Today's towns were built for running and cover: blocks shrink with the world, and the towns sit far apart in open meadow. Measured in the game:

At 0.65×, the hop between neighbouring towns sits right on the grapple's reach, so some routes link and some don't, by accident. That is what the townscape should decide on purpose.

• Heights follow the void line, so every world size plays alike. Houses stay human-sized at 4–8 m, for cover and climbing. Mid blocks reach a quarter to two-fifths of the void line (11–18 m at 0.65×, 17–27 m at 1×). One or two crowns per town reach 0.6–0.75 of it (27–33 m and 41–51 m), and spires stay at 0.86. Today blocks shrink with the world instead, which leaves big-world towns short.
• Crowns stand by the plaza. From the next town they are what you hook, and once you are in town their edges are the launchers out of it.
• Tighter cores. Streets 6–8 m wide, so rooftops chain within 15 m and a fight can move over the roofs. Plazas stay open, and towns thin out into gardens at their edges.
• Waypoint towers halfway along the 10 spokes to the poles and the 10 zigzags across the band, about half the void line tall (22 m at 0.65×). They cut the longest hop from 60 m to 33 m. A fling off a 22 m roof already throws you 111 m, past the 102 m between towns, so the towers are where you hook again mid-flight and keep going, and they mark the routes from afar. The 10 routes round each ring stay open meadow, crossed on foot, by pad or with one long throw.
• Two kinds of town round the rings. Urban towns with crowns and tight blocks alternate with garden towns, low and spread out. Regions then differ by townscape, as Landscape plans, and grapplers and walkers each get home ground.
• The void needs nothing new yet. The Heart is the roundabout and the drifters are the swings. Buoys, small floating rocks without wells, can come later if crossings need more stepping stones.

Taller, denser towns cost more to collide with, since every body checks every box at each step; collision moves onto the existing grid first. Bots will need to see ledges, or they will walk off roofs and get stuck more often.

Building it

1. The line, in the body step: the reel along the line, the fling and its bonus, the rope and the release. Bots share the step, so they get it for free later.
2. The gun: weapon 3, its view model and paws, the hook and cable out in the world, and its sounds.
3. Reading it: the reticle's states, the pin and the release arc.
4. Towns: heights by the void line, crowns and waypoints, behind a Towns setting (Classic or Grapple) until they play well. Collision moves onto the grid first.
5. Tests: flights in the game match this page, nobody sticks in a wall, bots still get around, and frame time holds with the taller towns.
6. Later: bots that grapple, a hook that holds bunnies, and a quick-fire hook from any weapon if swapping feels slow.

Next

The grapple gun is in the demo on key 3, with the numbers above and the mint ring that marks where the hook would bite. Spires are one column the deck's width now, so a hook never meets an overhang. Still to come: the dots that preview the throw at an edge, the reel's whir, stopping on a roof, bots that grapple, and the towns, behind their setting.

Open questions:

• A gun in slot 3, or a hook you can fire from any weapon, like Halo Infinite's equipment? This page assumes the gun.
• Should the hook hold bunnies, to pull an enemy in or ride along with a teammate?
• The new towns as the default, or behind a setting first?
• Stopping on a roof at speed: looking down as you go over clipped the edge in the first test. The fling may need to wait until you are over the roof when you look down.