diff --git a/BizHawk.Emulation.Cores/BizHawk.Emulation.Cores.csproj b/BizHawk.Emulation.Cores/BizHawk.Emulation.Cores.csproj
index e85ce537b2..336bb0e95b 100644
--- a/BizHawk.Emulation.Cores/BizHawk.Emulation.Cores.csproj
+++ b/BizHawk.Emulation.Cores/BizHawk.Emulation.Cores.csproj
@@ -551,6 +551,7 @@
+
diff --git a/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/Boards/Mapper213.cs b/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/Boards/Mapper213.cs
new file mode 100644
index 0000000000..4315b308f1
--- /dev/null
+++ b/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/Boards/Mapper213.cs
@@ -0,0 +1,60 @@
+using BizHawk.Common;
+using BizHawk.Common.NumberExtensions;
+
+namespace BizHawk.Emulation.Cores.Nintendo.NES
+{
+ // 9999999-in-1 [p2]
+ // http://wiki.nesdev.com/w/index.php/INES_Mapper_213
+ public class Mapper213 : NES.NESBoardBase
+ {
+ private int _reg;
+
+ public override bool Configure(NES.EDetectionOrigin origin)
+ {
+ switch (Cart.board_type)
+ {
+ case "MAPPER213":
+ break;
+ default:
+ return false;
+ }
+
+ SetMirrorType(Cart.pad_h, Cart.pad_v);
+
+ _reg = 65535;
+
+ return true;
+ }
+
+ public override void SyncState(Serializer ser)
+ {
+ base.SyncState(ser);
+ ser.Sync("_reg", ref _reg);
+ }
+
+ public override void WritePRG(int addr, byte value)
+ {
+ addr += 0x8000;
+
+ _reg = addr;
+ SetMirrorType(addr.Bit(3) ? EMirrorType.Vertical : EMirrorType.Horizontal);
+ }
+
+ public override byte ReadPRG(int addr)
+ {
+ int bank = (_reg >> 1) & 3;
+ return ROM[(bank * 0x8000) + (addr & 0x7FFF)];
+ }
+
+ public override byte ReadPPU(int addr)
+ {
+ if (addr < 0x2000)
+ {
+ int bank = (_reg >> 3) & 7;
+ return VROM[(bank * 0x2000) + (addr & 0x1FFF)];
+ }
+
+ return base.ReadPPU(addr);
+ }
+ }
+}