diff --git a/scripts/module.js b/scripts/module.js
index 0955de3..444370a 100644
--- a/scripts/module.js
+++ b/scripts/module.js
@@ -101,17 +101,37 @@ Hooks.on('renderSettingsConfig', (app, html, data) => {
 function isCriticalHit(roll) {
     if (!roll) return false;
 
-    // Check for Duality Roll
-    if (roll.constructor.name === "DualityRoll") {
+    // Check for Duality Roll (Class or Structure)
+    // DSN might pass a BaseRoll, so we check properties or terms
+    const isDuality = roll.constructor.name === "DualityRoll" ||
+        (roll.dHope && roll.dFear) ||
+        (roll.terms && roll.terms.filter(t => t.faces === 12).length === 2);
+
+    if (isDuality) {
         // Exclude reaction rolls
         const isReaction = roll.options?.actionType === "reaction";
-
         if (isReaction) return false;
 
-        // Check Hope == Fear
-        if (!roll.dHope?.total || !roll.dFear?.total) return false;
+        let hopeTotal, fearTotal;
 
-        return roll.dHope.total === roll.dFear.total;
+        if (roll.dHope?.total !== undefined && roll.dFear?.total !== undefined) {
+            hopeTotal = roll.dHope.total;
+            fearTotal = roll.dFear.total;
+        } else {
+            // Fallback: extract from terms
+            const d12s = roll.terms.filter(t => t.faces === 12);
+            if (d12s.length >= 2) {
+                // Assuming standard order or just checking equality
+                // In Duality, Hope and Fear are the two d12s. Equality is what matters.
+                hopeTotal = d12s[0].total;
+                fearTotal = d12s[1].total;
+            }
+        }
+
+        if (hopeTotal !== undefined && fearTotal !== undefined) {
+            console.log('Duality Check:', hopeTotal, fearTotal);
+            return hopeTotal === fearTotal;
+        }
     }
 
     // Check for standard d20 Roll (GM rolls mainly)
@@ -122,8 +142,8 @@ function isCriticalHit(roll) {
     return false;
 }
 
-// Hook into renderChatMessage to add CSS classes
-Hooks.on('renderChatMessage', (message, html, data) => {
+// Hook into renderChatMessageHTML (replacement for renderChatMessage)
+Hooks.on('renderChatMessageHTML', (message, html, data) => {
     // Only proceed if we have a roll
     if (!message.rolls || message.rolls.length === 0) return;