diff --git a/src/overlay.test.ts b/src/overlay.test.ts
index e96ed61..31ac006 100644
--- a/src/overlay.test.ts
+++ b/src/overlay.test.ts
@@ -1,5 +1,5 @@
 import { describe, it, expect } from "vitest";
-import { overlayStatus, reclassifyOverlay, pruneImports, attachRuntimeContainment } from "./overlay.ts";
+import { overlayStatus, reclassifyOverlay, pruneImports, attachRuntimeContainment, pruneRuntimeChildren } from "./overlay.ts";
 
 describe("overlayStatus", () => {
   it("maps chant's _status vocabulary to overlay statuses", () => {
@@ -134,3 +134,49 @@ describe("pruneImports", () => {
     expect(pruneImports(noImports).nodes).toHaveLength(1);
   });
 });
+
+// #86 — the runtime layer becomes a TIER, which means it has to be possible to
+// not descend. Before this, owner-referenced children were attached at every
+// zoom level, so a composites view carried its Pods.
+describe("pruneRuntimeChildren (#86)", () => {
+  const mixed = () => ({
+    nodes: [
+      { id: "web", kind: "K8s::Apps::Deployment", attrs: { _status: "good" } },
+      { id: "web-abc", kind: "K8s::Core::Pod", attrs: { _status: "runtime" }, runtimeOwner: "web" },
+      { id: "web-def", kind: "K8s::Core::Pod", attrs: { _status: "runtime" }, runtimeOwner: "web" },
+      { id: "svc", kind: "K8s::Core::Service", attrs: { _status: "good" } },
+    ],
+    edges: [
+      { from: "svc", to: "web" },
+      { from: "web-abc", to: "web" },
+    ],
+    groups: {},
+  });
+
+  it("drops runtime children, keeping every declared node", () => {
+    const out = pruneRuntimeChildren(mixed() as unknown as Parameters<typeof pruneRuntimeChildren>[0]);
+    expect(out.nodes.map((n) => n.id).sort()).toEqual(["svc", "web"]);
+  });
+
+  it("drops edges touching a removed node, so nothing dangles", () => {
+    const out = pruneRuntimeChildren(mixed() as unknown as Parameters<typeof pruneRuntimeChildren>[0]);
+    expect(out.edges).toEqual([{ from: "svc", to: "web" }]);
+  });
+
+  it("is a no-op on a graph with no owner chain — AWS and Azure are untouched", () => {
+    const aws = {
+      nodes: [{ id: "vpc", kind: "AWS::EC2::VPC", attrs: { _status: "good" } }],
+      edges: [{ from: "vpc", to: "vpc" }],
+      groups: {},
+    };
+    const before = JSON.stringify(aws);
+    expect(JSON.stringify(pruneRuntimeChildren(aws as unknown as Parameters<typeof pruneRuntimeChildren>[0]))).toBe(before);
+  });
+
+  it("is the inverse of attaching them — the two tiers show different graphs", () => {
+    const attached = attachRuntimeContainment(mixed() as unknown as Parameters<typeof attachRuntimeContainment>[0]);
+    const pruned = pruneRuntimeChildren(mixed() as unknown as Parameters<typeof pruneRuntimeChildren>[0]);
+    expect(attached.nodes.length).toBe(4);
+    expect(pruned.nodes.length).toBe(2);
+  });
+});
diff --git a/src/overlay.ts b/src/overlay.ts
index 7822f42..ba03f14 100644
--- a/src/overlay.ts
+++ b/src/overlay.ts
@@ -164,6 +164,29 @@ export function reclassifyOverlay<T extends { nodes: OverlayNode[] }>(ir: T): T
  * criterion that the tier is gracefully unavailable, never broken or blank.
  * Mutates + returns `ir`. Pure w.r.t. I/O.
  */
+/**
+ * Drop live-only runtime children from an overlay (#86).
+ *
+ * chant returns a Pod its Deployment's controller created as a node carrying
+ * `runtimeOwner` (chant#1180). Those nodes were attached at every zoom level,
+ * so a project's `composites` view carried its Pods — which is noise at that
+ * altitude, and meant the runtime layer could be seen but never dialled away.
+ *
+ * Making it a TIER means the other tiers stop where your source stops, which is
+ * what "descend below the declaration boundary" implies: you have to be able to
+ * not descend. Edges touching a dropped node go with it, since an edge to a node
+ * that is not in the graph renders as a dangling stub.
+ */
+export function pruneRuntimeChildren<T extends { nodes: OverlayNode[]; edges: Array<{ from: string; to: string }> }>(
+  ir: T,
+): T {
+  const runtime = new Set(ir.nodes.filter((n) => n.runtimeOwner).map((n) => n.id));
+  if (runtime.size === 0) return ir;
+  ir.nodes = ir.nodes.filter((n) => !runtime.has(n.id));
+  ir.edges = ir.edges.filter((e) => !runtime.has(e.from) && !runtime.has(e.to));
+  return ir;
+}
+
 export function attachRuntimeContainment<T extends { nodes: OverlayNode[]; groups: { byContainer?: Record<string, string[]> } }>(
   ir: T,
 ): T {
diff --git a/src/server.ts b/src/server.ts
index 94625bd..3a807bc 100644
--- a/src/server.ts
+++ b/src/server.ts
@@ -34,7 +34,7 @@ import {
   type ChantFailure,
 } from "./chant.ts";
 import { joinComponentStatus, componentStatusColor } from "./component-status.ts";
-import { reclassifyOverlay, pruneImports, attachRuntimeContainment } from "./overlay.ts";
+import { reclassifyOverlay, pruneImports, attachRuntimeContainment, pruneRuntimeChildren } from "./overlay.ts";
 import { addValueMatchEdges } from "./value-match.ts";
 import { addClusterAnchorEdges } from "./cluster-anchor.ts";
 import { projectTopology } from "./logical.ts";
@@ -728,7 +728,13 @@ export function createApp(
       // under its declared owner in `groups.byContainer` — a no-op on a
       // substrate with no owner chain. `renderGraph`'s `boxes: "byContainer"`
       // opt-in below draws it as a titled boundary box.
-      ir = attachRuntimeContainment(ir);
+      // The runtime tier (#86): `?runtime=1` descends below the declaration
+      // boundary and nests each owner-referenced child under its declared
+      // parent. Every other tier stops where your source stops — a Pod is noise
+      // in a composites view, and a layer you cannot dial away is not a tier.
+      ir = new URL(c.req.url).searchParams.get("runtime") === "1"
+        ? attachRuntimeContainment(ir)
+        : pruneRuntimeChildren(ir);
       // Logical/architecture lens (#63): re-project the live overlay into nested
       // region/VPC/subnet ⊃ component boxes, keeping each surviving node's drift
       // colour. Short-circuits the detail-tier pruning/composite plumbing below.
diff --git a/web/app.js b/web/app.js
index 4c37a64..a7eab2b 100644
--- a/web/app.js
+++ b/web/app.js
@@ -65,7 +65,7 @@ if (staticMode) {
 
 /** Canonical key for a read URL — path + the lens params (whitelisted, sorted)
  * that select a distinct snapshot. MUST match src/export.ts `canonicalKey`. */
-const LENS_PARAMS = ["components", "detail", "env", "logical", "radial", "tier"];
+const LENS_PARAMS = ["components", "detail", "env", "logical", "radial", "runtime", "tier"];
 function canonicalKey(path, params) {
   // Components + logical views ignore detail/radial — drop them so they match
   // the single captured snapshot (MUST match src/export.ts).
@@ -542,7 +542,7 @@ function wire(ir) {
 // null on a project that declares no `stacks[]` at all — the picker (and the
 // status strip's stack tag) then never renders. Every fetch reads this, so
 // the `changed` SSE re-pull and a palette lens change go through the same path.
-const view = { env: null, detail: 2, components: true, logical: false, tier: null, target: null, stack: null, radial: false };
+const view = { env: null, detail: 2, components: true, logical: false, runtime: false, tier: null, target: null, stack: null, radial: false };
 
 // v0.1.0 preview lock (set from /api/project in initActions): hides the git/PR
 // write ops (Rollback, Sync, Adopt, Run ▾) — the server also 403s them. Local
@@ -565,18 +565,25 @@ const ZOOM_OPTS = [
   ["zoom: composites", "composites"],
   ["zoom: resources", "resources"],
   ["zoom: attributes", "attributes"],
+  // Below the declaration boundary (#86): the owner-referenced children the
+  // cluster maintains — the Pods under a Deployment. Its own stop rather than a
+  // detail level, because it is a different axis: every tier above shows what
+  // you declared, and this one shows what your declaration produced.
+  ["zoom: runtime", "runtime"],
 ];
-const ZOOM_DETAIL = { composites: 1, resources: 2, attributes: 3 };
+const ZOOM_DETAIL = { composites: 1, resources: 2, attributes: 3, runtime: 3 };
 /** Current zoom value from (components, logical, detail). */
 function zoomValue() {
   if (view.components) return "components";
   if (view.logical) return "logical";
+  if (view.runtime) return "runtime";
   return { 1: "composites", 2: "resources", 3: "attributes" }[view.detail] ?? "resources";
 }
 /** Apply a zoom value back onto (components, logical, detail). */
 function applyZoom(z) {
   view.components = z === "components";
   view.logical = z === "logical";
+  view.runtime = z === "runtime";
   if (z !== "components" && z !== "logical") view.detail = ZOOM_DETAIL[z] ?? 2;
 }
 
@@ -1445,6 +1452,11 @@ async function load(opts = {}) {
     } else if (view.env) {
       endpoint = "/api/overlay";
       q.set("env", view.env);
+      // The runtime tier (#86) descends below the declaration boundary. It is
+      // live-only by nature — owner-referenced children exist in the cluster,
+      // never in your source — so it rides the overlay and means nothing
+      // without an env.
+      if (view.runtime) q.set("runtime", "1");
     }
     // Radial layout (entity view only) — curl the wide DAG onto concentric rings.
     if (view.radial && !view.components && !view.logical) q.set("radial", "1");