diff --git a/casino3d.inc b/casino3d.inc
--- a/casino3d.inc
+++ b/casino3d.inc
@@ -173,1 +173,2 @@
 include src_graphics\charms_data.inc
+include src_graphics\observer_data.inc
@@ -4856,5 +4857,5 @@
 check_target_observer:
     cmp eax, INTERACT_OBSERVER
     jne target_unported
-    call BeginUnavailable3D
+    call BeginObserver3D
     ret
@@ -5196,1 +5197,2 @@
 include src_graphics\charms.inc
+include src_graphics\observer.inc
@@ -5245,2 +5247,11 @@
     call ToggleFullscreen3D
 @@:
+    cmp obsActive3D,0
+    jne engine_observer_frame
+    cmp engineMode,MODE_OBSERVER
+    jne engine_observer_skip
+engine_observer_frame:
+    call UpdateMouseLockState
+    call ObserverFrame3D
+    jmp present_frame
+engine_observer_skip:
     invoke Pressed3D, 1Bh