diff --git a/ArcFormats/ArcFormats.csproj b/ArcFormats/ArcFormats.csproj
index edff1138..25505014 100644
--- a/ArcFormats/ArcFormats.csproj
+++ b/ArcFormats/ArcFormats.csproj
@@ -109,6 +109,7 @@
     <Compile Include="Cmvs\CpzHeader.cs" />
     <Compile Include="Cmvs\HuffmanDecoder.cs" />
     <Compile Include="Crowd\ImageCRZ.cs" />
+    <Compile Include="CsWare\ArcDAT.cs" />
     <Compile Include="CsWare\ImageBPC.cs" />
     <Compile Include="Cyberworks\ArcApp.cs" />
     <Compile Include="Cyberworks\ArcP8.cs" />
diff --git a/ArcFormats/CsWare/ArcDAT.cs b/ArcFormats/CsWare/ArcDAT.cs
new file mode 100644
index 00000000..c5da7009
--- /dev/null
+++ b/ArcFormats/CsWare/ArcDAT.cs
@@ -0,0 +1,137 @@
+//! \file       ArcDAT.cs
+//! \date       2017 Dec 21
+//! \brief      C's Ware BLITZ resource archive.
+//
+// Copyright (C) 2017 by morkt
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to
+// deal in the Software without restriction, including without limitation the
+// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+// sell copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+// IN THE SOFTWARE.
+//
+
+using System;
+using System.Collections.Generic;
+using System.ComponentModel.Composition;
+using System.Windows.Media;
+using GameRes.Compression;
+
+namespace GameRes.Formats.CsWare
+{
+    [Export(typeof(ArchiveFormat))]
+    public class PakOpener : ArchiveFormat
+    {
+        public override string         Tag { get { return "DAT/CSWARE"; } }
+        public override string Description { get { return "C's Ware BLITZ resource archive"; } }
+        public override uint     Signature { get { return 0; } }
+        public override bool  IsHierarchic { get { return false; } }
+        public override bool      CanWrite { get { return false; } }
+
+        public override ArcFile TryOpen (ArcView file)
+        {
+            int count = file.View.ReadInt32 (0);
+            if (!IsSaneCount (count))
+                return null;
+            uint packed_size = file.View.ReadUInt32 (4);
+            if (packed_size >= file.MaxOffset)
+                return null;
+            if (file.View.ReadByte (8) != 0x78) // zlib stream signature
+                return null;
+            long data_offset = 8 + packed_size;
+            using (var input = file.CreateStream (8, packed_size))
+            using (var unpacked = new ZLibStream (input, CompressionMode.Decompress))
+            using (var index = new BinaryStream (unpacked, file.Name))
+            {
+                var dir = new List<Entry> (count);
+                for (int i = 0; i < count; ++i)
+                {
+                    var name = index.ReadCString (0x18);
+                    if (string.IsNullOrEmpty (name))
+                        return null;
+                    var entry = FormatCatalog.Instance.Create<Entry> (name);
+                    entry.Offset = index.ReadUInt32() + data_offset;
+                    entry.Size   = index.ReadUInt32();
+                    if (!entry.CheckPlacement (file.MaxOffset))
+                        return null;
+                    dir.Add (entry);
+                }
+                return new ArcFile (file, this, dir);
+            }
+        }
+
+        public override IImageDecoder OpenImage (ArcFile arc, Entry entry)
+        {
+            if (entry.Size < 0x36 || !arc.File.View.AsciiEqual (entry.Offset, "BM"))
+                return base.OpenImage (arc, entry);
+            uint header_size = arc.File.View.ReadUInt32 (entry.Offset + 0xA);
+            if (header_size < 0x36 || header_size > entry.Size)
+                return base.OpenImage (arc, entry);
+            int height = arc.File.View.ReadInt32 (entry.Offset + 0x16);
+            var info = new BmMetaData {
+                Width = arc.File.View.ReadUInt32 (entry.Offset + 0x12),
+                Height = (uint)Math.Abs (height),
+                BPP = arc.File.View.ReadUInt16 (entry.Offset + 0x1C),
+                DataOffset = header_size,
+                IsFlipped = height > 0,
+                IsCompressed = arc.File.View.ReadUInt32 (0x32) != 0,
+            };
+            var input = arc.File.CreateStream (entry.Offset, entry.Size);
+            return new BmpDecoder (input, info);
+        }
+    }
+
+    internal class BmMetaData : ImageMetaData
+    {
+        public uint DataOffset;
+        public bool IsFlipped;
+        public bool IsCompressed;
+    }
+
+    internal class BmpDecoder : BinaryImageDecoder
+    {
+        public BmpDecoder (IBinaryStream input, BmMetaData info) : base (input, info)
+        {
+        }
+
+        protected override ImageData GetImageData ()
+        {
+            var meta = (BmMetaData)Info;
+            m_input.Position = meta.DataOffset;
+            int stride = (int)Info.Width * Info.BPP / 8;
+            var pixels = new byte[stride * (int)Info.Height];
+            if (meta.IsCompressed)
+            {
+                using (var unpacked = new ZLibStream (m_input.AsStream, CompressionMode.Decompress, true))
+                    unpacked.Read (pixels, 0, pixels.Length);
+            }
+            else
+            {
+                m_input.Read (pixels, 0, pixels.Length);
+            }
+            PixelFormat format;
+            if (24 == Info.BPP)
+                format = PixelFormats.Bgr24;
+            else if (32 == Info.BPP)
+                format = PixelFormats.Bgra32;
+            else
+                throw new InvalidFormatException();
+            if (meta.IsFlipped)
+                return ImageData.CreateFlipped (Info, format, null, pixels, stride);
+            else
+                return ImageData.Create (Info, format, null, pixels, stride);
+        }
+    }
+}