Bushranger's split tongue

Bushranger's split tongue, often simplified to just Split tongue and sometimes called Thieves' cant, is a secret codified language used by bushrangers and other people living in the underbelly of society to talk with each other.

As long as there are two criminals alive on the surface of Sahul, there will be people speaking Split tongue. Split tongue, much like evil, follows civilisation as a spectre of the darkness and greed inside of the hearts of man. Only once society has moved past the need for want and is capable of truly keeping every single person in comfort for his entire life, only then will Split tongue disappear.

Description
Split tongue allows two bushrangers to talk about their criminal activity while being right under the nose of the authorities without raising any suspicion. In Bushranger's split tongue almost every word has a double or split meaning, from which the language gets it name. Sentences can often sound strange our right out innocent to the uninitiated: but make no mistake, often these conversations discuss activities to horrid for the faint of heart to ever hear.

Script
Bushrangers often uses an book cipher when encrypting their messages to each other, with each letter represented by series of 6 numbers representing its place in the source text. These messages are often kept short but appear to outsiders to be extremely long because of the amount of space each letter takes in. Each group usually has a series of three to six books used in their ciphers, with the number of the book being hidden in the margins of the message. When out in the field Split tongue uses symbols depicting the local fauna to hide messages in plain sight. For example a Crocodile represent dangerous authorities while an dingo means that the locals are cowardly and that one can get away with more than they usually would.

Vocabulary
To bleach To kill

Carp Loot

Pick up Assassinate

Plate Guard

Bunch of plates in the way Well protected

Pretty Valuable, well payed

This friend Target

To herd To steal

Tree Fortress

Phrases
I want to herd some carps from the tree, but there are a bunch of plates in the way, could you help me? I need you for a heist on the fortress, it is well protected.

'''I want you to pick up this pretty friend of me. Yeah the redheaded Moon Elf. Try not to bleach any plates.''' I am hiring you to assassinate a redheaded Moon Elf without killing any of the guards. I will pay you well.