diff --git a/challenges/cache-pressure-easy/statement.json b/challenges/cache-pressure-easy/statement.json
index fafeb82..3ed3ce5 100644
--- a/challenges/cache-pressure-easy/statement.json
+++ b/challenges/cache-pressure-easy/statement.json
@@ -8,16 +8,10 @@
     {
       "kind": "figure",
       "label": "FIG 1",
+      "presentation": "immersive",
       "illustration": {
-        "id": "systems.snapshot",
-        "props": {
-          "title": "Oldest on the left · newest on the right",
-          "rows": [
-            { "label": "After two puts", "cells": [{ "label": "A", "detail": "oldest", "tone": "warning" }, { "label": "B", "detail": "newest", "tone": "accent" }] },
-            { "label": "Get A", "cells": [{ "label": "B", "detail": "oldest", "tone": "warning" }, { "label": "A", "detail": "newest", "tone": "signal" }], "note": "A hit changes order without fetching from the backing store." },
-            { "label": "Put C", "cells": [{ "label": "A", "detail": "oldest", "tone": "accent" }, { "label": "C", "detail": "newest", "tone": "signal" }], "note": "B leaves because it was least recently used." }
-          ]
-        }
+        "id": "systems.cache-story",
+        "props": { "mode": "lru" }
       },
       "caption": "One hit changes the eviction decision. This two-entry example illustrates order; real capacity counts each value's bytes plus metadata."
     },
diff --git a/challenges/cache-pressure-medium/statement.json b/challenges/cache-pressure-medium/statement.json
index 19b6df7..a39e873 100644
--- a/challenges/cache-pressure-medium/statement.json
+++ b/challenges/cache-pressure-medium/statement.json
@@ -8,16 +8,10 @@
     {
       "kind": "figure",
       "label": "FIG 1",
+      "presentation": "immersive",
       "illustration": {
-        "id": "systems.snapshot",
-        "props": {
-          "title": "What a one-time scan does to a small cache",
-          "rows": [
-            { "label": "Warm", "cells": [{ "label": "H1", "tone": "signal" }, { "label": "H2", "tone": "signal" }, { "label": "H3", "tone": "signal" }], "note": "The hot set is reused often." },
-            { "label": "Cold scan", "cells": [{ "label": "S1", "tone": "warning" }, { "label": "S2", "tone": "warning" }, { "label": "S3", "tone": "warning" }], "note": "Pure LRU fills the budget with one-hit keys." },
-            { "label": "Return", "cells": [{ "label": "H1 miss", "tone": "danger" }, { "label": "H2 miss", "tone": "danger" }, { "label": "H3 miss", "tone": "danger" }], "note": "A protected hot segment would keep these requests cheap." }
-          ]
-        }
+        "id": "systems.cache-story",
+        "props": { "mode": "scan" }
       },
       "caption": "Pure LRU mistakes recent for reusable. A one-time scan looks important long enough to evict the data that will actually return."
     },
diff --git a/challenges/lossy-link-easy/statement.json b/challenges/lossy-link-easy/statement.json
index 5c7a648..5e517d4 100644
--- a/challenges/lossy-link-easy/statement.json
+++ b/challenges/lossy-link-easy/statement.json
@@ -8,20 +8,10 @@
     {
       "kind": "figure",
       "label": "FIG 1",
+      "presentation": "immersive",
       "illustration": {
-        "id": "systems.exchange",
-        "props": {
-          "title": "A lost ACK is why duplicates must be safe",
-          "left": "Sender",
-          "right": "Receiver",
-          "events": [
-            { "from": "left", "label": "DATA 0 · abc", "detail": "deliver abc", "tone": "signal" },
-            { "from": "right", "label": "ACK 0", "detail": "waiting", "dropped": true, "tone": "danger" },
-            { "from": "local", "label": "timer fires", "tone": "warning" },
-            { "from": "left", "label": "DATA 0 · retry", "detail": "duplicate, no delivery", "tone": "warning" },
-            { "from": "right", "label": "ACK 0 again", "detail": "advance to 1", "tone": "accent" }
-          ]
-        }
+        "id": "systems.lost-ack-story",
+        "props": {}
       },
       "caption": "Loss or corruption leaves the sender waiting. When its timer fires, it retransmits the same packet; the receiver discards duplicates but repeats the ACK."
     },