The grapple

Hook, hold, let go

• Hook. The trigger fires a three-clawed grapnel along your aim. It catches on anything built or floating within 56 m: buildings, spires, drifters and their huts, and the Heart. Grass, trees and bunnies don't hold it, and a miss reels straight back at no cost.
• Hold. The reel pulls you toward the hook at 60 m/s², almost three times the ground's pull, up to 28 m/s, and you keep the speed you already had. While the line is taut, gravity can't pull you below it, so you fly along the line you see.
• Up and over the edge. When the hook catches an edge, the reel aims 3 m above it, so you clear the wall and pass over. If you aim at the top third of a wall, 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 the way you look, never below level, with nine-tenths of your speed plus 0.3 m/s for every metre you were from the hook when it caught (9 m/s from 29 m). Hooking from far and looking up gives a big throw, and hooking from close gives a hop.
• Let go. You can let go any time and keep your speed. Letting go partway along a long pull is how a spire throws you across the world.
• Wells. On a drifter or the Heart, the line holds you like a rope 3 m above the surface. Your speed carries you round, and because the reel and the well both pull inward, each turn gets faster. Let go when you face where you want to go.
• Two hooks. You have two charges, and each comes back 3 s after use. Crossing a gate cuts the line.

The reach scales with the world at 0.575 of the radius, just enough to reach the Heart from any spire deck (the table below has the distances), 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, and 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 stops speeding you up at 28 m/s, and extra speed comes from circling a well.
• Overwatch's Wrecking Ball. The claw's anchor becomes a pendulum to build speed from, and it can attach only to things that don't move or break (Overwatch Wiki). Wells work the same way here, and so does the hook.
• Batman: Arkham. The grapple boost flings Batman off the ledge he pulled to, so the city can be crossed without touching the ground (PlayStation Blog). The edge fling is that move, aimed where you look.
• Sekiro. A grapple point in range pulls you straight onto the building or branch above it, clear of the wall, and some points launch you forward the way you face (Twinfinite, Siliconera), as this grapple does.
• 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), and our towns below get the same tuning for the grapple.
• 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 catch, on the roof edge if it is going to climb, and nothing shows when nothing in reach would hold it.
• While you hold. Near an edge, dots show where the fling would throw you for the way you are looking. Away from edges, the usual fall arc shows where you would land if you let go now.

The gun

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

Firing kicks the gun and spins the reel out, and the hook catches with a clank; letting go reels it back into the mouth with a click. Like every gun in the game, its bore runs parallel to your view, so it points at the reticle.

It is weapon 3, on the 3 key or the wheel.

Towns as anchors

Today's towns were built for running and cover: their blocks don't grow as fast as the world does, and the towns sit far apart in open meadow. These are the numbers measured in the game:

At 0.65×, the hop between neighbouring towns is about the grapple's reach, so some routes link up by accident and some don't, and the townscape should decide that 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.
• Crowns stand by the plaza. From the next town you hook the crowns, and in town their edges launch you out.
• Tighter cores. Streets are 6–8 m wide, so each rooftop is within 15 m of the next and a fight can move across the roofs. Plazas stay open, and towns thin out into gardens at their edges.
• Waypoint towers stand 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, farther than the 102 m between towns, so the towers are places to hook again mid-flight, and they mark the routes from far away. The 10 routes round each ring stay open meadow, crossed on foot, by pad or in one long throw.
• Two kinds of town round the rings. Urban towns with crowns and tight blocks alternate with garden towns, which are low and spread out. So regions differ by townscape, as Landscape plans, with places for both grapplers and walkers.
• The void needs nothing new yet. Buoys, small floating rocks without wells, can come later if crossings need more places to hook.

Building it

1. The line, in the body step: the reel along the line, the fling and its bonus, the rope and the release.
2. The gun: weapon 3, its view model and paws, the hook and cable, 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, because every body checks every box at each step, which costs more in taller, denser towns.
5. Tests: flights in the game match this page, nobody sticks in a wall, bots see ledges and still get around, and the frame rate stays steady with the taller towns.

Next

The grapple gun is in the demo, with the numbers above and the mint ring. Spires are now a single column as wide as the deck, so a hook never meets an overhang. Still to come: the dots that preview the throw at an edge, a reel whir that rises with speed, stopping on a roof, bots that grapple, and the towns, behind their setting.

Open questions:

• Should the grapple be 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?
• Should the new towns be the default, or sit behind a setting first?
• How should you stop on a roof at speed? In the first test, looking down as you went over made you clip the edge, so the fling may need to wait until you are over the roof.