Generally speaking, Star Wars Jedi: Fallen Order keeps a pretty tight lock on lightsaber colours. While you start off with a choice between traditional Jedi blue and green (or orange, if you splashed out on the bougie pre-order edition), there's never an option to go full Sith - and you can't unlock further colours until much later in the game.
As a big fan of Star Wars: The Old Republic - a game with a ridiculously varied collection of lightsaber crystals - I was curious to see whether someone would mod Fallen Order to accommodate these wacky combos. Sure enough, it's already been done: but the process is a little fiddly, and hasn't yet been streamlined into easily-downloadable mod form (of the sort you'd find on Nexus Mods).
Using third-party freeware Cheat Engine to edit the game, PC modders have written a script which allows users to tinker with the lightsaber's colour settings. By altering values in the code using the RGB colour model (and some hex), it's possible to create colours and combine them in different layers of the lightsaber for some funky designs - including black core lightsabers.
Naturally, I had to have a go. Apologies for the dire combat performance in parts of the video, I was somewhat distracted by the pretty colours.
The first of my experiments involved testing the boundaries of the values: what happens on either end of the zero to one scale, or when you enter a value larger than one? A chonky lightsaber, that's what, and entering a number of around ten results in a fluffy-looking saber, which somehow still does damage. Maybe Cal just tickles the stormtroopers to death.
Setting all the values to one results in a bright white, while bringing it down to zero gets you black - perfect for some darksaber experiments. I managed to make both a traditional monochrome darksaber, some more colourful variations, and a totally black saber, which looks rather sinister and is also impossible to see when you're in a cave. Personally, I'm a big fan of the black core with blue glow.
Next, it was time to get really colourful, and I spent some time tweaking the sabers to create bright yellow, hot pink, and a hideous green-purple - which I'm pretty sure is not canon. The pastel pink and blue looks cute, but I found the best combinations are created by using several layers of colours which are near to each other on the spectrum, as this gives them a more vibrant look.
The script also allows users to change individual blades on Cal's double-bladed lightsaber, so I threw together red and blue. As the lightsaber was probably never intended to hold two colours, the external "glow" normally extends across the whole saber, so I had to remove it to prevent red light from shining out the blue end. It's giving me big Beat Saber vibes.
Finally, of course, I had to do some Sith-style red sabers. Cal must have finally snapped after being dunked on by Ogdo Bogdo for the tenth time in a row.
While using the Cheat Engine script was fun, it wasn't the fastest process, and changing the colours took a lot of tweaking. There was the problem with out-of-control glow, while the script creators haven't yet discovered how to change the colour of sparks on impact - meaning it's currently just a blue-white. On top of this, the changes I made weren't persistent, so I had to re-edit each time I booted up the game.
Still, I had a lot of fun - and it felt great to mess around with darksabers and black core lightsabers. Perhaps surprisingly for some, despite the relatively recent Disney purge of Star Wars Expanded Universe lore, darksabers have actually remained a part of franchise canon. One appeared in the Clone Wars TV series, for example (wielded by Pre Vizsla and a variety of other people, and briefly travelling to Dathomir). That darksaber was created by the first Jedi Mandalorian Tarre Vizsla, which is quite a timely bit of lore. No word on baby Yoda mods just yet.