msfvenom [options] <var=val>

-l, --list            <type>     List all modules for [type]. Types are: payloads, encoders, nops, platforms, archs, encrypt, formats, all
-p, --payload         <payload>  Payload to use (--list payloads to list, --list-options for arguments). Specify '-' or STDIN for custom
    --list-options               List --payload <value>'s standard, advanced and evasion options
-f, --format          <format>   Output format (use --list formats to list)
-e, --encoder         <encoder>  The encoder to use (use --list encoders to list)
    --service-name    <value>    The service name to use when generating a service binary
    --sec-name        <value>    The new section name to use when generating large Windows binaries. Default: random 4-character alpha string
    --smallest                   Generate the smallest possible payload using all available encoders
    --encrypt         <value>    The type of encryption or encoding to apply to the shellcode (use --list encrypt to list)
    --encrypt-key     <value>    A key to be used for --encrypt
    --encrypt-iv      <value>    An initialization vector for --encrypt
-a, --arch            <arch>     The architecture to use for --payload and --encoders (use --list archs to list)
    --platform        <platform> The platform for --payload (use --list platforms to list)
-o, --out             <path>     Save the payload to a file
-b, --bad-chars       <list>     Characters to avoid example: '\x00\xff'
-n, --nopsled         <length>   Prepend a nopsled of [length] size on to the payload
    --pad-nops                   Use nopsled size specified by -n <length> as the total payload size, auto-prepending a nopsled of quantity (nops minus payload length)
-s, --space           <length>   The maximum size of the resulting payload
    --encoder-space   <length>   The maximum size of the encoded payload (defaults to the -s value)
-i, --iterations      <count>    The number of times to encode the payload
-c, --add-code        <path>     Specify an additional win32 shellcode file to include
-x, --template        <path>     Specify a custom executable file to use as a template
-k, --keep                       Preserve the --template behaviour and inject the payload as a new thread
-v, --var-name        <value>    Specify a custom variable name to use for certain output formats
-t, --timeout         <second>   The number of seconds to wait when reading the payload from STDIN (default 30, 0 to disable)
-h, --help                       Show this message