This is basically a reminder for me but could be useful for anyone. I keep forgetting how to convert commands to a Powershell compatible encoded string:
From the command line:
echo "iex(command)" | iconv --to-code UTF-16LE | base64 -w 0
For Python:
from base64 import b64encode
b64encode('iex(command)'.encode('UTF-16LE'))
For Ruby:
require "base64"
Base64.encode64('iex(command)'.force_encoding('UTF-16LE'))