diff --git a/GameServer/Server/CallGS/Handlers/Rogue3D/Rogue3D_CheckOpenAct.cs b/GameServer/Server/CallGS/Handlers/Rogue3D/Rogue3D_CheckOpenAct.cs
new file mode 100644
index 0000000..14947af
--- /dev/null
+++ b/GameServer/Server/CallGS/Handlers/Rogue3D/Rogue3D_CheckOpenAct.cs
@@ -0,0 +1,13 @@
+namespace MikuSB.GameServer.Server.CallGS.Handlers.Rogue3D;
+
+// Returns which Rogue3D acts (server_04_timelist) are currently open.
+// param: [] (empty)
+// Response: {"listActId":[...]}
+[CallGSApi("Rogue3D_CheckOpenAct")]
+public class Rogue3D_CheckOpenAct : ICallGSHandler
+{
+    public async Task Handle(Connection connection, string param, ushort seqNo)
+    {
+        await CallGSRouter.SendScript(connection, "Rogue3D_CheckOpenAct", "{\"bOpen\":true}");
+    }
+}