Genesis Earthion encryption

[ilker2495]

Decryption script for the latest 4.0.0 version dropped. Once again by SharpNull at the Emu-Land forums. I am linking the script here. Once again I will be describing how to use it. You need to own Earthion on Steam to use this:

Spoiler: Instructions

Step 1: Go to the 7-zip website, from the sidebar, select "LZMA SDK", download the latest version. Unzip it. Inside you'll want to go to the "bin" folder and find lzma.exe. Place this in a folder.
Step 2: Right click on Earthion on Steam, choose "Manage > Browse local files". Go to the folder called "Data". That's where game.bin is going to be. Go ahead and place it in this folder as well, right next to lzma.exe.
Step 3: Install Python 3 from the official Python website if you haven't already. Make sure to choose "Add to PATH variable" before you start the installation.
Reminder: You now have a folder that has the following files all right next to each other: lzma.exe, earthion unpack script, game.bin.
Step 4: Open command prompt here. Run "py earthion_unpack_v4.0.0.py". Wait until it's done.

My gratitudes to SharpNull for continuously providing decryption scripts for this lovely game, allowing us to play it in our favorite emulators with no input lag and all the customizations we could want. Have fun!

 

[IrkenElite]

I bought the game last steam sale. Thanks for saving us the effort.

 

[John Karmack]

When I tried it, the script crashed because it called int.from_bytes (and then to_bytes) without the mandatory byteorder argument, so Python did not know how to interpret the raw bytes.

To fix, change line 90 to:
v += int.to_bytes(int.from_bytes(vec_enc[off:off+3], 'big') << 1, 4, 'big')

Also, no lzma.exe helper utility is required because the script imports the lzma module directly.

 

[Goshikk]

my destitute ass waiting for this game to show up on the repo

 

[ilker2495]

When I tried it, the script crashed because it called int.from_bytes (and then to_bytes) without the mandatory byteorder argument, so Python did not know how to interpret the raw bytes.

To fix, change line 90 to:
v += int.to_bytes(int.from_bytes(vec_enc[off:off+3], 'big') << 1, 4, 'big')

Also, no lzma.exe helper utility is required because the script imports the lzma module directly.

When I put lzma.exe next to the script I get no issues. Maybe the guy writing the script wrote it for the lzma.exe helper? I'm not knowledgeable so I just copy what he suggests people do. Thanks for the analysis and fix.

 

[newageretrohippie]

anybody know what's new in the 4.0 version?

(my brother has the steam game, and valve has determined with their superior algorithm that we, are in fact, NOT family, so he has to grab the rom for me while i wait for the genesis cartridge which i can actually own)

Post automatically merged: Nov 4, 2025

my destitute ass waiting for this game to show up on the repo
View attachment 124593

I *might* be playing shantae advanced in a try-before-i buy type of scenario... I swear i got locked in some kind or room or something tho last time i played it... i just turned it off, cause i wasn't sure what to do..

I wonder if it has some anti-piracy weird stuff ala spyro.. like, i dare not ask anywhere but here. heh

(although i actually bought 5 separate copies of "pirate's curse" and 2 copies of... uhh.. "that other shantae game that wasn't very good".. so you would think i would be sort of entitled.. haha)

 

[ilker2495]

anybody know what's new in the 4.0 version?

The biggest change is a fix to bullet visibility. They removed the color green from the bullet flashes, making them more readable. It's now slightly closer to the eXa-Arcadia version of Earthion, though not the same. I find this to be a huge reason to upgrade to 4.0.0

Below is a changelog taken from Ancient Co.'s Japanese Twitter account.

• Resolving unpredictable bugs caused by spark bits.
• Remove the green color of enemy bullets.
• Adjusted the background for better visibility in the latter half of Stage 5.
• Added Challenge 7 and 8.

 

[newageretrohippie]

The biggest change is a fix to bullet visibility. They removed the color green from the bullet flashes, making them more readable. It's now slightly closer to the eXa-Arcadia version of Earthion, though not the same. I find this to be a huge reason to upgrade to 4.0.0

Below is a changelog taken from Ancient Co.'s Japanese Twitter account.

oh, yeah that is a real problem. especially on stage 2. oh my god. i can't tell what's going on against those clouds. i always talk to koshiro on X i thought about saying something about it.