Prerequisites

This guide assumes you are using Debian 10, it might work on other distros but you might need to do tweaks in which you are on your own.

It also assumes you already have OSRS official client available. If you don't, you can refer to this guide.

Guide

One thing you should keep in mind is that Simba has some quirks on Linux. There's nothing too serious but I already accept it as normal to have errors popping up when scripts are terminating.

So let's begin!

First we want to install a couple of dependencies Simba has and make the directory we will use for it :

sudo apt install libxtst-dev gtk2.0 libgtk2.0-dev libffi-dev
mkdir ~/Simba

Now we have to download Simba-Linux64 and optionally you can download Simba logo to see it in your desktop when you are done.

wget -O ~/Simba/Simba-Linux64 https://github.com/ollydev/Simba/releases/latest/download/Simba-Linux64
wget -O ~/Simba/Simba.ico https://raw.githubusercontent.com/ollydev/Simba/simba1400/Source/Simba/Simba.ico

Finally we have to make Simba-Linux64 executable:

chmod +x ~/Simba/Simba-Linux64

With that you should have a fully functional Simba installation. There's a caveat though. In this state, remote input will not work. That is fine if you don't use it, but if you do you have 2 solutions:

Run Simba as root

Install libcap2-bin and use setcap

The first solution is easy to do but it's not a good approach and creates a lot of issues with permissions because every file modified by Simba run as root, becomes a root file. So I would recommend you to with the second proper solution and install libcap2-bin and use setcap cap_sys_ptrace=eip on Simba:

sudo apt install libcap2-bin -y
sudo setcap cap_sys_ptrace=eip ~/Simba/Simba-Linux64

Now you have a truly functional Simba on Linux.

You can now optionally make Desktop entry for it to be accessible, otherwise you need to run it from the terminal:

echo 'alias simba="/home/username/Simba/Simba-Linux64"' | sudo tee --append /etc/bash.bashrc
echo '[Desktop Entry]' | sudo tee --append /usr/share/applications/simba.desktop
echo 'Type=Application' | sudo tee --append /usr/share/applications/simba.desktop
echo 'Name=Simba' | sudo tee --append /usr/share/applications/simba.desktop
echo 'Comment=Simba 1400' | sudo tee --append /usr/share/applications/simba.desktop
echo 'Exec=~/Simba/Simba-Linux64' | sudo tee --append /usr/share/applications/simba.desktop
echo 'Icon=/home/username/Simba/Simba.ico' | sudo tee --append /usr/share/applications/simba.desktop
echo 'Categories=Game' | sudo tee --append /usr/share/applications/simba.desktop
echo 'MimeType=text/simba;text/graph;' | sudo tee --append /usr/share/applications/simba.desktop
echo 'Terminal=false' | sudo tee --append /usr/share/applications/simba.desktop
echo 'Keywords=Simba;RuneScape;' | sudo tee --append /usr/share/applications/simba.desktop

Make sure to change username to your username!

And that's it. sudo reboot and you are done!

Below you have a list of all the commands needed for easy copy paste in the future:

sudo apt install libxtst-dev gtk2.0 libgtk2.0-dev libffi-dev libcap2-bin -y

mkdir ~/Simba
wget -O ~/Simba/Simba.ico https://raw.githubusercontent.com/ollydev/Simba/simba1400/Source/Simba/Simba.ico
wget -O ~/Simba/Simba-Linux64 https://github.com/ollydev/Simba/releases/download/autobuild-simba1400/Simba-Linux64

chmod +x ~/Simba/Simba-Linux64
sudo setcap cap_sys_ptrace=eip ~/Simba/Simba-Linux64

echo 'alias simba="/home/username/Simba/Simba-Linux64"' | sudo tee --append /etc/bash.bashrc
echo '[Desktop Entry]' | sudo tee --append /usr/share/applications/simba.desktop
echo 'Type=Application' | sudo tee --append /usr/share/applications/simba.desktop
echo 'Name=Simba' | sudo tee --append /usr/share/applications/simba.desktop
echo 'Comment=Simba 1400' | sudo tee --append /usr/share/applications/simba.desktop
echo 'Exec=~/Simba/Simba-Linux64' | sudo tee --append /usr/share/applications/simba.desktop
echo 'Icon=/home/username/Simba/Simba.ico' | sudo tee --append /usr/share/applications/simba.desktop
echo 'Categories=Game' | sudo tee --append /usr/share/applications/simba.desktop
echo 'MimeType=text/simba;text/graph;' | sudo tee --append /usr/share/applications/simba.desktop
echo 'Terminal=false' | sudo tee --append /usr/share/applications/simba.desktop
echo 'Keywords=Simba;RuneScape;' | sudo tee --append /usr/share/applications/simba.desktop