Enable mixed selected-deck Discovery previews

docs/DISCOVERY_PROTOTYPE.md

@@ -1,5 +1,21 @@
 # Discovery functional prototype
 
+## Mixed selected-deck Discovery alone — 29 October 2026
+
+**Prototyped / Partial.** Basic and Advanced previews can use Discovery with
+selected Ecaz/Moritani, Ixians/Tleilaxu and/or CHOAM/Richese decks without
+requiring Nexus or the independent Ecaz cards. A selected deck need not have a
+seated native faction. Existing Tech3+ and Advanced Stronghold prerequisites,
+unrelated overlay restrictions and the Advanced Moritani/Harkonnen boundary
+remain. The Ecaz/Moritani paired arrival retains its provisional storm order;
+its Fremen/Guild Ambassador-created child restrictions are still separate.
+
+Thirteen related files pass 82 cases. Public-start Basic and Advanced fixtures
+exercise original Ixian setup and shipment, an actual Discovery blow, Duke
+acquisition and Robbery with legal bot choices. Unopened Spice order and original
+Ambassador/Terror placement are controlled. Other optional-module interactions,
+complete games and deployed verification remain open.
+
 ## Ecaz and Moritani with Discovery alone — 29 October 2026
 
 **Prototyped / Partial.** A fresh Basic or Advanced preview can select both