diff --git a/README.md b/README.md
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+# libhac
+
+libhac is a .NET or .NET Core library for opening, decrypting and extracting common content file formats used by the Nintendo Switch.
+
+All content is imported and exported as .NET streams. This means that reading nested file types and encryptions can easily be done by linking different file readers together.  
+For example, the files from a title stored on the external SD card can be read or extracted in this way.  
+`NAX0 Reader` -> `NCA Reader` -> `RomFS Reader` -> `Individual Files`
+
+# hactoolnet
+
+hactoolnet is an example program that uses libhac. It is used in a similar manner to [hactool](https://github.com/SciresM/hactool).
+
+## Usage
+```
+Usage: hactoolnet [options...] <path>
+Options:
+  -r, --raw            Keep raw data, don't unpack.
+  -y, --verify         Verify hashes.
+  -k, --keyset         Load keys from an external file.
+  -t, --intype=type    Specify input file type [nca, switchfs]
+  --titlekeys <file>   Load title keys from an external file.
+NCA options:
+  --section0 <file>    Specify Section 0 file path.
+  --section1 <file>    Specify Section 1 file path.
+  --section2 <file>    Specify Section 2 file path.
+  --section3 <file>    Specify Section 3 file path.
+  --section0dir <dir>  Specify Section 0 directory path.
+  --section1dir <dir>  Specify Section 1 directory path.
+  --section2dir <dir>  Specify Section 2 directory path.
+  --section3dir <dir>  Specify Section 3 directory path.
+  --listromfs          List files in RomFS.
+  --basenca            Set Base NCA to use with update partitions.
+Switch FS options:
+  --sdseed <seed>      Set console unique seed for SD card NAX0 encryption.
+  --listapps           List application info.
+  --listtitles         List title info for all titles.
+  --title <title id>   Specify title ID to use.
+  --outdir <dir>       Specify directory path to save title to.
+  --romfsdir <dir>     Specify RomFS directory path.
+```
+
+## Examples
+
+#### List applications on a Switch SD card or NAND
+`hactoolnet -t switchfs --sdseed <sd_seed> --listapps <sd_root_path>`
+
+#### Extract a title from an SD card or NAND as NCA files
+`hactoolnet -t switchfs --sdseed <sd_seed> --title <title_id> --outdir output <sd_root_path>`
+
+#### Extract the RomFS from a title from an SD card or NAND
+`hactoolnet -t switchfs --sdseed <sd_seed> --title <title_id> --romfsdir romfs <sd_root_path>`
+
+Specifying the base title ID will extract the unpatched title.  
+Specifying the patch title ID will extract the patched title.
+
+## External Keys
+
+Keys can be loaded from a text file by specifying a filename with the `-k` argument. The file should be in the same format read by [hactool](https://github.com/SciresM/hactool#external-keys):  
+"Keyset files are text files containing one key per line, in the form "key_name = HEXADECIMALKEY". Case shouldn't matter, nor should whitespace."
+
+Title keys can be loaded from a text file by specifying a filename with the `--titlekeys` argument. The file should contain one key per line in the form `rights_id,HEXADECIMALKEY`.
+
+If a keyfile is not set at the command line, hactoolnet will search for and load keyfiles in `$HOME/.switch/prod.keys` and `$HOME/.switch/titlekeys.txt`.
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diff --git a/hactoolnet/CliParser.cs b/hactoolnet/CliParser.cs
index 85ce897e..ad9a90a3 100644
--- a/hactoolnet/CliParser.cs
+++ b/hactoolnet/CliParser.cs
@@ -149,6 +149,7 @@ namespace hactoolnet
             sb.AppendLine("  --section2dir <dir>  Specify Section 2 directory path.");
             sb.AppendLine("  --section3dir <dir>  Specify Section 3 directory path.");
             sb.AppendLine("  --listromfs          List files in RomFS.");
+            sb.AppendLine("  --basenca            Set Base NCA to use with update partitions.");
             sb.AppendLine("Switch FS options:");
             sb.AppendLine("  --sdseed <seed>      Set console unique seed for SD card NAX0 encryption.");
             sb.AppendLine("  --listapps           List application info.");