The Dark Lord had, of course, spent those three days meditating in the wild -- taking the time to do something he'd put off for a good while.
Constructing a holocron.
All of his, of course, were now in Ashin's possession, and in the custody of the Master of Vaults, Lord Dissero. And thus, he needed to make a new one. Holocron craftsmanship was, so far as he was aware, a skill which nobody else had mastered in the modern era, and he needed to keep those skills sharp.
"The history of that blade is contained in this holocron," he said, activating it. "I've put a very specific set of knowledge into it. Everything I know about Djem So combat, everything I know about enhancing your body with the Force. Skills like this can't be learned in days or weeks; they need to be honed over a lifetime. This holocron will stand you in good stead. Take it.
"In simplest terms, the blade was made by an old friend of mine, a master alchemist named Darth Kharonos. It's simple durasteel, but strengthened and sharpened by powerful alchemy -- that's what gives it that pale colour. It will repel a lightsabre, and its grip and hilt are insulated against lightning. It's one of the finest swords ever made, in my opinion. It gives you no special powers; it's a simple, straightforward tool. It's known as the Pale Blade.
"That sword once tasted the blood of Ashin Varanin. One of her many scars. I used that blade against her while she cast down the Sith'ari Centrality, and the Pale Blade is the weapon I used when she struck me down. May it serve you better than it served me."