diff --git a/src/10th/Roster.jsx b/src/10th/Roster.jsx
index 9af97c1..8b22454 100644
--- a/src/10th/Roster.jsx
+++ b/src/10th/Roster.jsx
@@ -562,7 +562,7 @@ const Unit = ({
 };
 
 const checkAbilitiesForInvul = (abilitiesMap, name) => {
-	const abilities = [...abilitiesMap.keys()];
+	const abilities = [...(abilitiesMap?.keys?.() || [])];
 	for (let ability of abilities) {
 		if (ability.includes(":")) {
 			// if : then only match if the name is the same