diff --git a/challenges/chunk-store-easy/statement.json b/challenges/chunk-store-easy/statement.json
index fafc1f9..c59e599 100644
--- a/challenges/chunk-store-easy/statement.json
+++ b/challenges/chunk-store-easy/statement.json
@@ -9,16 +9,10 @@
       "kind": "figure",
       "label": "FIG 1",
       "illustration": {
-        "id": "systems.frames",
-        "props": {
-          "title": "One blob · independently readable frames",
-          "note": "ReadAt uses the index to select a frame",
-          "frames": [
-            { "label": "Block 0", "status": "not read", "tone": "neutral", "fields": [{ "label": "header", "detail": "lengths", "tone": "neutral" }, { "label": "AAAA", "detail": "payload", "tone": "neutral" }, { "label": "CRC", "detail": "integrity", "tone": "neutral" }] },
-            { "label": "Block 1", "status": "read + verified", "tone": "signal", "fields": [{ "label": "header", "detail": "lengths", "tone": "accent" }, { "label": "BCDE", "detail": "requested CD", "tone": "signal" }, { "label": "CRC", "detail": "checked", "tone": "warning" }], "note": "Offset 5, length 2 touches only this block in the example below." }
-          ]
-        }
+        "id": "systems.chunk-story",
+        "props": {}
       },
+      "presentation": "immersive",
       "caption": "Compression and integrity are block-local. That locality is what makes exact random reads cheap and bounded."
     },
     {
diff --git a/challenges/deadline-scheduler-easy/statement.json b/challenges/deadline-scheduler-easy/statement.json
index 6ab5172..609d490 100644
--- a/challenges/deadline-scheduler-easy/statement.json
+++ b/challenges/deadline-scheduler-easy/statement.json
@@ -9,19 +9,10 @@
       "kind": "figure",
       "label": "FIG 1",
       "illustration": {
-        "id": "systems.ranges",
-        "props": {
-          "title": "One worker · three non-preemptive jobs",
-          "min": 0,
-          "max": 11,
-          "rows": [
-            { "label": "A", "start": 0, "end": 6, "tone": "warning", "note": "Starts at 0; cannot be interrupted when B and C arrive." },
-            { "label": "B", "start": 6, "end": 8, "tone": "signal", "note": "Waits until the worker becomes idle." },
-            { "label": "C", "start": 8, "end": 11, "tone": "accent", "note": "Ordering is chosen only at an idle boundary." }
-          ],
-          "markers": [{ "at": 1, "label": "C arrives", "tone": "danger" }, { "at": 6, "label": "A done", "tone": "signal" }]
-        }
+        "id": "systems.scheduler-story",
+        "props": {}
       },
+      "presentation": "immersive",
       "caption": "Once A starts it owns the worker until tick 6. Better ordering happens only at idle boundaries."
     },
     {
diff --git a/challenges/durable-queue-easy/statement.json b/challenges/durable-queue-easy/statement.json
index a9674ac..cd2fa39 100644
--- a/challenges/durable-queue-easy/statement.json
+++ b/challenges/durable-queue-easy/statement.json
@@ -9,16 +9,10 @@
       "kind": "figure",
       "label": "FIG 1",
       "illustration": {
-        "id": "systems.snapshot",
-        "props": {
-          "title": "FIFO is defined by when a job becomes available",
-          "rows": [
-            { "label": "Enqueue", "cells": [{ "label": "A", "detail": "ready", "tone": "accent" }, { "label": "B", "detail": "ready", "tone": "accent" }] },
-            { "label": "Lease A", "cells": [{ "label": "B", "detail": "ready", "tone": "accent" }, { "label": "A", "detail": "leased until 10", "tone": "warning" }], "note": "A still occupies capacity while leased." },
-            { "label": "Nack A", "cells": [{ "label": "B", "detail": "next", "tone": "signal" }, { "label": "A", "detail": "back of queue", "tone": "accent" }], "note": "A's old token is now stale." }
-          ]
-        }
+        "id": "systems.queue-story",
+        "props": {}
       },
+      "presentation": "immersive",
       "caption": "Nack or visibility expiry returns a leased job to the back of the available queue. It receives a fresh token when leased again."
     },
     {
diff --git a/challenges/fair-gate-easy/statement.json b/challenges/fair-gate-easy/statement.json
index 849aeb7..b96704f 100644
--- a/challenges/fair-gate-easy/statement.json
+++ b/challenges/fair-gate-easy/statement.json
@@ -9,18 +9,10 @@
       "kind": "figure",
       "label": "FIG 1",
       "illustration": {
-        "id": "systems.budget",
-        "props": {
-          "title": "A burst of four tokens · refill two per three ticks",
-          "capacity": 4,
-          "snapshots": [
-            { "label": "tick 0 · full", "segments": [{ "label": "available", "value": 4, "tone": "signal" }] },
-            { "label": "tick 0 · after cost 3", "segments": [{ "label": "available", "value": 1, "tone": "warning" }], "note": "a second cost-3 request is rejected" },
-            { "label": "tick 3 · before retry", "segments": [{ "label": "available", "value": 3, "tone": "signal" }], "note": "two tokens accrued lazily" },
-            { "label": "tick 3 · after retry", "segments": [{ "label": "available", "value": 0, "tone": "accent" }], "note": "the retry is now admitted" }
-          ]
-        }
+        "id": "systems.gate-story",
+        "props": {}
       },
+      "presentation": "immersive",
       "caption": "No timer updates the bucket in the background. Each request first accounts for elapsed virtual time, then makes one deterministic decision."
     },
     {