diff --git a/core/src/com/unciv/models/ruleset/Ruleset.kt b/core/src/com/unciv/models/ruleset/Ruleset.kt
index b8cd0c5dca..48bb69c743 100644
--- a/core/src/com/unciv/models/ruleset/Ruleset.kt
+++ b/core/src/com/unciv/models/ruleset/Ruleset.kt
@@ -348,7 +348,7 @@ class Ruleset {
             for (promotion in unit.promotions)
                 if (!unitPromotions.containsKey(promotion))
                     lines += "${unit.name} contains promotion $promotion which does not exist!"
-            if (!unitTypes.containsKey(unit.unitType) && !baseRuleset.unitTypes.containsKey(unit.unitType))
+            if (!unitTypes.containsKey(unit.unitType) && (unitTypes.isNotEmpty() || !baseRuleset.unitTypes.containsKey(unit.unitType)))
                 lines += "${unit.name} is of type ${unit.unitType}, which does not exist!"
             for (unique in unit.getMatchingUniques("Can construct []")) {
                 val improvementName = unique.params[0]