diff --git a/ArcFormats/ArcFormats.csproj b/ArcFormats/ArcFormats.csproj
index f1aa6acd..0631bda4 100644
--- a/ArcFormats/ArcFormats.csproj
+++ b/ArcFormats/ArcFormats.csproj
@@ -284,6 +284,7 @@
+
diff --git a/ArcFormats/FrontWing/ArcDAT.cs b/ArcFormats/FrontWing/ArcDAT.cs
new file mode 100644
index 00000000..9abbb8bb
--- /dev/null
+++ b/ArcFormats/FrontWing/ArcDAT.cs
@@ -0,0 +1,104 @@
+//! \file ArcDAT.cs
+//! \date 2025-12-13
+//! \brief FrontWing resource archive.
+//
+// Copyright (C) 2018 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.IO;
+using GameRes.Utility;
+
+namespace GameRes.Formats.FrontWing
+{
+ [Export(typeof(ArchiveFormat))]
+ public class DatOpener : ArchiveFormat
+ {
+ public override string Tag { get { return "DAT/TIMELEAP"; } }
+ public override string Description { get { return "'Time Leap' 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)
+ {
+ if (file.MaxOffset < 4)
+ return null;
+ int count = file.View.ReadInt32 (file.MaxOffset - 4);
+ if (!IsSaneCount (count))
+ return null;
+
+ int index_size = 0x50 * count;
+ if (file.MaxOffset < index_size + 4)
+ return null;
+ var index = file.View.ReadBytes (file.MaxOffset - 4 - index_size, (uint)index_size);
+ NibbleSwap (index);
+
+ int index_offset = 0;
+ var dir = new List (count);
+ for (int i = 0; i < count; i++)
+ {
+ var name = Binary.GetCString (index, index_offset, 0x40);
+ var entry = Create (name);
+ entry.Offset = LittleEndian.ToUInt32 (index, index_offset + 0x40);
+ entry.Size = LittleEndian.ToUInt32 (index, index_offset + 0x48);
+ if (!entry.CheckPlacement (file.MaxOffset))
+ return null;
+ index_offset += 0x50;
+ dir.Add (entry);
+ }
+ return new ArcFile (file, this, dir);
+ }
+
+ static readonly byte[] keyTable = {
+ 0xff, 0xff, 0xff, 0x01,
+ 0x9c, 0xaa, 0xa5, 0x00,
+ 0x30, 0xff, 0x77, 0x00,
+ 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00
+ };
+
+ public override Stream OpenEntry (ArcFile arc, Entry entry)
+ {
+ var data = arc.File.View.ReadBytes (entry.Offset, entry.Size);
+ for (int i = 1; i < data.Length; i += 4)
+ {
+ data[i] = (byte)(-data[i] & 0xff);
+ }
+ for (int i = 0; i < data.Length; i += 3)
+ {
+ data[i] ^= keyTable[i / 5 % 5 + i % 6];
+ }
+ NibbleSwap(data, 2, 6);
+ return new BinMemoryStream (data);
+ }
+
+ void NibbleSwap (byte[] buffer, int start = 0, int step = 1)
+ {
+ for (int i = start; i < buffer.Length; i += step)
+ {
+ buffer[i] = (byte)(((buffer[i] & 0xf0) >> 4) + ((buffer[i] & 0xf) << 4));
+ }
+ }
+ }
+}