Events

nexBash communicates over the Nexus eventStream global — the canonical listener interface for cross-package integrations. Other packages subscribe the same way they would to any Nexus topic:

eventStream.registerEvent(
  "nexbash4.target.selected",
  (target) => {
    console.log("nexBash engaged", target.name);
  },
  { id: "my-package:target-selected", tags: ["my-package"] },
);

All listeners nexBash itself registers are tagged ["nexBash"] (plus a more specific tag) so they can be bulk-removed across machine restarts, strategy switches, and area changes.

Topics nexBash emits

These nexbash4.* topics are nexBash's outbound contract. An integration may rely on them.

Target and combat

Topic	Payload	Emitted when
nexbash4.target.selected	the chosen target object	A target is selected to engage.
nexbash4.target.gotShield	the target	The active target raised a shield.
nexbash4.npc.lostShield	the razed NPC	A combatant's shield came down (raze or observed loss).
nexbash4.target.lost	none	The active target left the room or died.
nexbash4.target.slain	none	The active target was killed.

Area and run

Topic	Payload	Emitted when
nexbash4.started	{ area }	A run went live. Fires once per run (not on an actor-reuse restart), so it pairs 1:1 with nexbash4.stopped.
nexbash4.stopped	{ area, summary }	A run went inert on any route — manual stop(), a STOP event, or area-clear self-completion. Fires once per run; summary is the final { kills, gold, elapsedMs } scoreboard.
nexbash4.area.cleared	the active Area	The bashing run completed (for routed areas). Precedes the run's nexbash4.stopped.
nexbash4.room.cleared	GMCP.Room.Info	The current room holds no targets — a fresh room with nothing spawned yet, or the last target just died. Fires every time checkingForTargets confirms this, so it may repeat for the same room.
nexbash4.discovery.recorded	{ areaKey, areaName, npc, field, value, source }	A new mob observation was recorded mid-run, such as an observed damage range.
nexbash4.discovery.report	{ reason, area, discoveries }	A run ended (reason is "manualStop" or "areaClear"); reports the run's discoveries.
nexbash4.quest.chain.complete	none	A scripted quest chain finished.

Effect timers

The transient-effect expiry timers (bloodcloak, maya, deathcape) emit a scoped lifecycle topic per timer id:

Topic	Emitted when
nexbash4.timer.started.<id>	The timer started or re-armed.
nexbash4.timer.reset.<id>	The timer was reset.
nexbash4.timer.stopped.<id>	The timer elapsed (the effect winds down).

<id> is bloodcloak, maya, or deathcape. nexBash listens to its own *.stopped.<id> topics to mark the matching effect unavailable.

Topics nexBash reacts to

nexBash is primarily a consumer of host state. It subscribes to the following topics from nexSys4, nexMap, and the raw Nexus/GMCP stream. These are listed for context — they are owned by those packages, not by nexBash.

Always-on (application level)

Topic	nexBash's reaction
nexsys4.system.class.changed	Re-select the class strategy.
nexmap4.area.changed	Resolve and apply the area for the new location.
IRE.Misc.Achievement	Update the session kill count and re-arm effect timers.
IRE.Target.Info	Update the active target's HP.
nexSkillMatch.<skill>	Track crowd-control landing on a target (stormbolt, dilation, ague, scorch, psidaze, deaden, temperance, stagnate, cleanseaura).
nexsys4.aff.got / nexsys4.aff.lost	Drive the bloodcloak → bloodshield automation.
nexsys4.def.got.bloodshield / .lost.bloodshield	Drive the bloodcloak automation.
PromptEvent	One-shot Loki affliction probe and gold collection.
nexbash4.target.selected	Pre-draw morimbuul and run per-area target customizations.

Combat-scoped (only while a run is live)

The bash machine subscribes these only in its combat state and tears them down on exit:

Topic	nexBash's reaction
PromptEvent	Per-prompt attack selection.
battlerageUpdate / nexsys4.def.got.freerage / nexsys4.system.rage.changed	Re-run autonomous battlerage selection.
nexSkillMatch	Track razes and battlerage ability/balance consumption.
IRE.Display.ButtonActions	Track per-ability battlerage availability.
nexsys4.item.room.added / .removed	Detect a mob entering or the target leaving/dying.
nexmap4.room.changed / nexmap4.pathing.start / nexmap4.pathing.complete	Drive room re-scan and pathing updates.
Room.Players	Re-evaluate room contest and target count.
nexsys4.system.paused / .unpaused	Pause / resume the run.
nexsys4.def.got.shield / .got.prismatic / nexsys4.aff.got.aeon	Suspend offence and clear offence queues.

Contract notes

• battlerageUpdate is an internal signal nexBash raises to poke its own rage re-evaluation; it is not a nexbash4.* topic and is not a stable integration point.
• Effect-timer topics are scoped by id; subscribe to the specific nexbash4.timer.stopped.bloodcloak form, not a wildcard.
• nexBash never freezes, clones, or deletes from the global GMCP object — it is the shared source of truth for the whole client.