Support unused selected decks with Nexus and Discovery

docs/DISCOVERY_PROTOTYPE.md

@@ -1,5 +1,14 @@
 # Discovery functional prototype
 
+## Selected but unused E3 deck — 29 October 2026
+
+**Prototyped / Partial.** A fresh Basic or Advanced preview can select only
+the E3 faction deck with Discovery while seating classic factions alone, without
+Nexus or independent Ecaz cards. The same original seven Spice Cards and eight
+tokens are initialized. Public-start fixtures reach an actual Discovery Spice
+Blow with controlled unopened card order and legal bot choices. Optional
+interactions, complete games and deployed verification remain open.
+
 ## Mixed selected-deck Discovery alone — 29 October 2026
 
 **Prototyped / Partial.** Basic and Advanced previews can use Discovery with