diff --git a/src/unittest/CMakeLists.txt b/src/unittest/CMakeLists.txt
index 8a635c8e8..7417819bd 100644
--- a/src/unittest/CMakeLists.txt
+++ b/src/unittest/CMakeLists.txt
@@ -16,6 +16,7 @@ set (UNITTEST_SRCS
 	${CMAKE_CURRENT_SOURCE_DIR}/test_irr_matrix4.cpp
 	${CMAKE_CURRENT_SOURCE_DIR}/test_irr_rotation.cpp
 	${CMAKE_CURRENT_SOURCE_DIR}/test_logging.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/test_lbmmanager.cpp
 	${CMAKE_CURRENT_SOURCE_DIR}/test_lua.cpp
 	${CMAKE_CURRENT_SOURCE_DIR}/test_map.cpp
 	${CMAKE_CURRENT_SOURCE_DIR}/test_mapblock.cpp
diff --git a/src/unittest/test_lbmmanager.cpp b/src/unittest/test_lbmmanager.cpp
new file mode 100644
index 000000000..6f3627331
--- /dev/null
+++ b/src/unittest/test_lbmmanager.cpp
@@ -0,0 +1,82 @@
+// Luanti
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2025 sfan5
+
+#include "test.h"
+
+#include <sstream>
+
+#include "serverenvironment.h"
+
+class TestLBMManager : public TestBase
+{
+public:
+	TestLBMManager() { TestManager::registerTestModule(this); }
+	const char *getName() {	return "TestLBMManager"; }
+
+	void runTests(IGameDef *gamedef);
+
+	void testNew(IGameDef *gamedef);
+	void testExisting(IGameDef *gamedef);
+	void testDiscard(IGameDef *gamedef);
+};
+
+static TestLBMManager g_test_instance;
+
+void TestLBMManager::runTests(IGameDef *gamedef)
+{
+	TEST(testNew, gamedef);
+	TEST(testExisting, gamedef);
+	TEST(testDiscard, gamedef);
+}
+
+namespace {
+	struct FakeLBM : LoadingBlockModifierDef {
+		FakeLBM(const std::string &name, bool every_load) {
+			this->name = name;
+			this->run_at_every_load = every_load;
+			trigger_contents.emplace_back("air");
+		}
+	};
+}
+
+void TestLBMManager::testNew(IGameDef *gamedef)
+{
+	LBMManager mgr;
+
+	mgr.addLBMDef(new FakeLBM(":foo:bar", false));
+	mgr.addLBMDef(new FakeLBM("not:this", true));
+
+	mgr.loadIntroductionTimes("", gamedef, 1234);
+
+	auto str = mgr.createIntroductionTimesString();
+	// name of first lbm should have been stripped
+	// the second should not appear at all
+	UASSERTEQ(auto, str, "foo:bar~1234;");
+}
+
+void TestLBMManager::testExisting(IGameDef *gamedef)
+{
+	LBMManager mgr;
+
+	mgr.addLBMDef(new FakeLBM("foo:bar", false));
+
+	// colon should also be stripped when loading (due to old versions)
+	mgr.loadIntroductionTimes(":foo:bar~22;", gamedef, 1234);
+
+	auto str = mgr.createIntroductionTimesString();
+	UASSERTEQ(auto, str, "foo:bar~22;");
+}
+
+void TestLBMManager::testDiscard(IGameDef *gamedef)
+{
+	LBMManager mgr;
+
+	// LBMs that no longer exist are dropped
+	mgr.loadIntroductionTimes("some:thing~2;", gamedef, 10);
+
+	auto str = mgr.createIntroductionTimesString();
+	UASSERTEQ(auto, str, "");
+}
+
+// We should also test LBMManager::applyLBMs in the future.