Zippers
Zippers are expendable devices that force nearby live mines to detonate. They do not disarm mines or create a protective field. A ship needs a zipper launcher and one zipper in its inventory; see Zip command for launch syntax, restrictions, range differences, and reload behavior.
What happens to the mines
A launch checks every live mine against the launching ship's position. Each mine strictly within zipper trigger range has its countdown reset to 1, even if it belongs to the launcher or has no active owner. A mine outside that range is unchanged. No zipper projectile remains in space after launch, and one zipper can affect many mines at once.
On the next global mine update, each triggered timer drops from 1 to 0 and the mine detonates at its own position. Mine updates normally occur about every six seconds, so the wait can be nearly immediate or almost a full update interval. Until that update, the mine is still live; the zipper does not make the route safe instantly. Triggering a mine also does not move or enlarge its blast. Ships strictly within the mine's 10,000-distance-unit blast radius at detonation can be hit, regardless of which ship fired the zipper. A ship caught within several blasts can take multiple hits on the same update. See Mines for mine damage and proximity warnings.
Trigger range
The range test measures each mine from the launching ship, independently of the mine's 10,000-unit blast radius. In classic GE, the intended limit is the launcher class's configured scanner range. The helper uses the launcher position but mistakenly reads the range from the global current-player ship. A player's own ZIPPER command uses matching pointers, but an NPC launch can borrow another ship's class range, triggering too few or too many mines. See Classic bug: NPC zipper uses another ship's scanner range.
ge-next uses the launching ship's effective scanner range. Enhanced scanners double that range; ge-arena's reduced scan range in two- or three-player matches reduces it. Nebulas can conceal mines from a scan but do not shorten the physical trigger range. A mine must be strictly inside that range, not exactly on its boundary.
Tactical use and risks
A ship can clear a prospective route by triggering mines while it is outside their blast radii, then waiting for the detonations before entering. It can also set off mines near a pursuer before that ship moves away. Because the test uses each mine's distance from the launcher, not the intended victim, the launcher must itself be close enough to trigger them and can be caught in the explosions. The game does not tell the launcher how many mines were affected or where they are.
A zipper cannot choose mine owners. Friendly, hostile, and ownerless mines are all eligible. Launching a zipper does not transfer ownership of a mine to the launcher: damage and possible kill credit follow the ordinary mine rules, including ge-next's ownerless-mine handling after a player leaves. The launcher can therefore be hurt by its own mines without gaining credit merely for setting off another player's mines. In the protected neutral zone, triggered mines expire on schedule but cannot damage protected ships. See Neutral zone for the version-specific protection rules.
Supply and NPC use
Zippers are cargo items, not a renewable ship system. In the stock classic and ge-next configuration, one weighs five tons and has a base price of 99 credits; sysops can change those values. Ships can carry or trade them like other eligible items, while the launcher capability depends on ship class. A successful launch consumes one even when no mines were in range.
Cybertrons can launch zippers in both versions; equipped droids gain zipper use in ge-next. Classic Cybertrons decide whether to launch from mines near themselves and temporarily create one zipper for the launch. In ge-next, Cybertrons and zipper-equipped droids may decide to launch when their target has mines nearby, but zip() still triggers mines near the NPC launcher. These positions need not coincide, so a launch can affect no mines. ge-next NPCs consume carried zippers and share the one-ship-update launcher reload delay. The resulting explosions follow ordinary mine rules. See Zip command for the player command and Classic bug: NPC zipper uses another ship's scanner range for the classic range error.
See also
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