diff --git a/lords_of_ash/common/game_rules/00_mistborn_game_rules.txt b/lords_of_ash/common/game_rules/00_mistborn_game_rules.txt
new file mode 100644
index 0000000..0c3272f
--- /dev/null
+++ b/lords_of_ash/common/game_rules/00_mistborn_game_rules.txt
@@ -0,0 +1,13 @@
+mistborn_game_mode = {
+	default = mistborn_game_mode_narrative_mode
+
+	mistborn_game_mode_narrative_mode = {
+		# Curated story arcs following the book's plot
+		# Narrative events fire, some decisions restricted
+	}
+	mistborn_game_mode_sandbox_mode = {
+		# Play any character, full freedom
+		# "Discover Your Metallic Arts" decision available
+		# Narrative events suppressed
+	}
+}
diff --git a/lords_of_ash/localization/english/mistborn_game_rules_l_english.yml b/lords_of_ash/localization/english/mistborn_game_rules_l_english.yml
new file mode 100644
index 0000000..2edee3f
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+++ b/lords_of_ash/localization/english/mistborn_game_rules_l_english.yml
@@ -0,0 +1,7 @@
+l_english:
+ mistborn_game_mode:0 "Game Mode"
+ mistborn_game_mode_desc:0 "Choose between a curated Mistborn story experience or an open sandbox."
+ mistborn_game_mode_narrative_mode:0 "Narrative Mode"
+ mistborn_game_mode_narrative_mode_desc:0 "Experience the story of Mistborn: The Final Empire. Curated events will fire based on story progression. Recommended for first playthrough."
+ mistborn_game_mode_sandbox_mode:0 "Sandbox Mode"
+ mistborn_game_mode_sandbox_mode_desc:0 "Play as any character with full freedom. The 'Discover Your Metallic Arts' decision is available. Narrative story events are suppressed."