From 786102c43e090d83dceebab5389a1b83a6c19111 Mon Sep 17 00:00:00 2001
From: com55 <33087300+com55@users.noreply.github.com>
Date: Wed, 5 Aug 2026 21:49:49 +0700
Subject: [PATCH 1/2] fix(BundleFile): correct packer tuple docstring and add
 lz4hc preset

The save(packer=...) docstring listed the custom tuple as (block_info_flag, data_flag), but save_fs(writer, *packer) expects (data_flag, block_info_flag).

LZ4HC compression was already wired through CompressionHelper; add packer="lz4hc" (data_flag=195, block_info_flag=3) and update the stale "not implemented" comment.
---
 UnityPy/environment.py      | 2 +-
 UnityPy/files/BundleFile.py | 9 +++++++--
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/UnityPy/environment.py b/UnityPy/environment.py
index c4a60aea..5425b9aa 100644
--- a/UnityPy/environment.py
+++ b/UnityPy/environment.py
@@ -176,7 +176,7 @@ def load_zip_file(self, value):
     def save(self, pack="none", out_path="output"):
         """Saves all changed assets.
         Mark assets as changed using `.mark_changed()`.
-        pack = "none" (default) or "lz4"
+        pack = "none" (default), "lz4", "lz4hc", "lzma", or "original"
         """
         for fname, fitem in self.files.items():
             if getattr(fitem, "is_changed", False):
diff --git a/UnityPy/files/BundleFile.py b/UnityPy/files/BundleFile.py
index 3e17d7de..55390af5 100644
--- a/UnityPy/files/BundleFile.py
+++ b/UnityPy/files/BundleFile.py
@@ -191,10 +191,12 @@ def save(self, packer=None):
 
         packer:
             can be either one of the following strings
-            or tuple consisting of (block_info_flag, data_flag)
+            or tuple consisting of (data_flag, block_info_flag)
             allowed strings:
                 none - no compression, default, safest bet
                 lz4 - lz4 compression
+                lz4hc - lz4hc compression
+                lzma - lzma compression
                 original - uses the original flags
         """
         # file_header
@@ -227,6 +229,8 @@ def save(self, packer=None):
                 )
             elif packer == "lz4":
                 self.save_fs(writer, data_flag=194, block_info_flag=2)
+            elif packer == "lz4hc":
+                self.save_fs(writer, data_flag=195, block_info_flag=3)
             elif packer == "lzma":
                 self.save_fs(writer, data_flag=65, block_info_flag=1)
             elif isinstance(packer, tuple):
@@ -242,12 +246,13 @@ def save_fs(self, writer: EndianBinaryWriter, data_flag: int, block_info_flag: i
 
         # 0b1000000 / 0b11000000 | 64 / 192 - uncompressed
         # 0b11000010 | 194 - lz4
+        # 0b11000011 | 195 - lz4hc
         # block_info_flag
 
         # 0 / 0b1000000 | 0 / 64 - uncompressed
         # 0b1   | 1 - lzma
         # 0b10  | 2 - lz4
-        # 0b11  | 3 - lz4hc [not implemented]
+        # 0b11  | 3 - lz4hc
         # 0b100 | 4 - lzham [not implemented]
         # data_flag
 

From 1a8dcd075cf1598cff1ad1113efad64a0c61b6cd Mon Sep 17 00:00:00 2001
From: com55 <33087300+com55@users.noreply.github.com>
Date: Wed, 5 Aug 2026 23:22:14 +0700
Subject: [PATCH 2/2] docs(Environment): clarify pack options depend on file
 type

Environment.save forwards pack to every file's save(); BundleFile and
WebFile accept different packer values, so do not list BundleFile-only
presets as if they were universal.
---
 UnityPy/environment.py | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/UnityPy/environment.py b/UnityPy/environment.py
index 5425b9aa..08ea909f 100644
--- a/UnityPy/environment.py
+++ b/UnityPy/environment.py
@@ -176,7 +176,11 @@ def load_zip_file(self, value):
     def save(self, pack="none", out_path="output"):
         """Saves all changed assets.
         Mark assets as changed using `.mark_changed()`.
-        pack = "none" (default), "lz4", "lz4hc", "lzma", or "original"
+
+        ``pack`` is forwarded as ``packer`` to each file's ``save()``.
+        Supported values depend on the file type, for example:
+            BundleFile - "none", "lz4", "lz4hc", "lzma", "original"
+            WebFile - "none", "gzip", "brotli"
         """
         for fname, fitem in self.files.items():
             if getattr(fitem, "is_changed", False):