diff --git a/BizHawk.Emulation.Cores/BizHawk.Emulation.Cores.csproj b/BizHawk.Emulation.Cores/BizHawk.Emulation.Cores.csproj
index 78c263119a..34bbe55fec 100644
--- a/BizHawk.Emulation.Cores/BizHawk.Emulation.Cores.csproj
+++ b/BizHawk.Emulation.Cores/BizHawk.Emulation.Cores.csproj
@@ -644,6 +644,7 @@
     <Compile Include="Consoles\Nintendo\NES\Boards\UNIF\UNIF_BMC-GS-2013.cs" />
     <Compile Include="Consoles\Nintendo\NES\Boards\UNIF\UNIF_BMC-T-262.cs" />
     <Compile Include="Consoles\Nintendo\NES\Boards\UNIF\UNIF_UNL-AX5705.cs" />
+    <Compile Include="Consoles\Nintendo\NES\Boards\UNIF\UNIF_UNL-CC-21.cs" />
     <Compile Include="Consoles\Nintendo\NES\Boards\UxROM.cs">
       <SubType>Code</SubType>
     </Compile>
diff --git a/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/Boards/UNIF/UNIF_UNL-CC-21.cs b/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/Boards/UNIF/UNIF_UNL-CC-21.cs
new file mode 100644
index 0000000000..991e5b2907
--- /dev/null
+++ b/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/Boards/UNIF/UNIF_UNL-CC-21.cs
@@ -0,0 +1,60 @@
+using BizHawk.Common;
+using BizHawk.Common.NumberExtensions;
+
+namespace BizHawk.Emulation.Cores.Nintendo.NES
+{
+	public class UNIF_UNL_CC_21 : NES.NESBoardBase
+	{
+		int _reg;
+		public override bool Configure(NES.EDetectionOrigin origin)
+		{
+			switch (Cart.board_type)
+			{
+				case "UNIF_UNL-CC-21":
+					break;
+				default:
+					return false;
+			}
+
+			return true;
+		}
+
+		public override void WritePRG(int addr, byte value)
+		{
+			if (addr == 0) // FCEUX says: another one many-in-1 mapper, there is a lot of similar carts with little different wirings
+			{
+				_reg = value;
+			}
+			else
+			{
+				_reg = addr;
+			}
+
+			SetMirrorType(addr.Bit(0) ? EMirrorType.OneScreenB : EMirrorType.OneScreenA);
+		}
+
+		public override void SyncState(Serializer ser)
+		{
+			base.SyncState(ser);
+			ser.Sync("reg", ref _reg);
+
+		}
+
+		public override byte ReadPPU(int addr)
+		{
+			if (addr < 0x2000)
+			{
+				if (Cart.chr_size == 8192)
+				{
+					return VROM[((_reg & 1) * 0xFFF) + (addr & 0xFFF)];
+				}
+				else // Some bad, overdumped roms made by cah4e3
+				{
+					return VROM[((_reg & 1) * 0x2000) + (addr & 0x1FFF)];
+				}
+			}
+
+			return base.ReadPPU(addr);
+		}
+	}
+}