diff --git a/lightshow/_tests/conftest.py b/lightshow/_tests/conftest.py
index 09f4e4d7..2bda12fc 100644
--- a/lightshow/_tests/conftest.py
+++ b/lightshow/_tests/conftest.py
@@ -62,7 +62,7 @@ def _database_for_stress_test():
     # "mp-1208324", "mp-10734"]
     # return Database.from_materials_project(material_ids=trouble)
     # return Database.from_materials_project(material_ids=["mp-980945"])
-    db = Database.from_materials_project(chemsys=["Ti-*"])
+    db = Database.from_materials_project(chemsys=["Ti-*", "Mn-O-*"])
     # db = Database.from_materials_project(material_ids=["mp-390"])
     keys = list(db._structures.keys())
     # random.seed(123)