This guide is work in progress. Please report any issues you may encounter and other feedback on github.

Marenthyu's Guide to Custom Firmware using SeedMiner

Required Reading

Welcome! You have come here, i guess, on the prospect of installing custom Firmware on your new/old Nintendo 2DS/3DS using the single-System Nintendo DSiWare Injection. This means you do not have one of the following things:

and you are on system firmware version 11.4 or newer (The newest one currently being 11.6).
WARNING! This guide is only for firmware versions between 11.4 to 11.6. If you are on a newer firmware this method might not work or even damage your device. I take no responsibility for any damages to your device.

You may have come here not fully knowing what SeedMiner is and how it works. Click the following button if you want to see more information:

What is SeedMiner?

SeedMiner is a tool that allows you to brute-force a console-unique Key. It utilises your Graphics Card's amazing processing power to try out all possible combinations, with one of them being guaranteed to work.
Using this key (or "seed"), it is possible to then sign a DSiWare Game which has been modified to run an exploit on your Device when launching it.

This all is only possible thanks to a flaw in the key calculation, which makes it (almost) predictable - more information on the nitty-gritty details can be found on zoogie's explanation slide here, but long story short: using your LCFS (Local Friend-Code Seed), it is possible to predict your movable.sed key with an accuracy of about +-4000, which we then can "easily" brute-force.

In addition to getting everything you will need to get your movable.sed, this guide will also recommend you a few tools which you can then use to actually inject your modified Game/Save onto your console.
In most cases, you will be able to use an automated service, but if that fails you, you may need to try one of the other tools available to you.


This guide will, at all times, attempt to be as thorough as possible, but i can not guarantee it to be understandable 100% of the time. If you have a question and/or don't understand something, don't hesitate to ask.
In General, you have the following help sources:

  1. The seedminer GBATemp Thread
  2. The Seedminer FC and mining help GBATemp Thread
  3. Me, Marenthyu, on Discord.

If you ask for help there, please make sure to tell the persons there that you are coming from this guide, giving them this link.

Still here? Good! Please continue with the next step.