diff --git a/doc/gamedesign.md b/doc/gamedesign.md
index a8a5b61..1576569 100644
--- a/doc/gamedesign.md
+++ b/doc/gamedesign.md
@@ -55,6 +55,8 @@ We are not quite there yet, but this is what I'm aiming for:
     - No requirement for Steam or any other environment
     - No loading screens
     - No save games
+        - This one is really tough though, because a lot of fun comes from being able to unlock things like suit upgrades, radio stations, phone numbers to call NPCs, etc.
+        - Maybe just a minimal savegameoid which is just a list of things that have been unlocked, which can be reset from the menu easily?
     - No need to remember anything
     - Simple inventory system
     - Packaged for major Linux distributions and gaming environments