"I see the beginnings of a powerful Lord of the Sith in you, apprentice."
He had not seen such potential since his most promising student, Darth Pyrrhus, who had become one of his proudest disciples and a fervent adherent of his philosophy. Carnifex reached out and grasped Valeska by the shoulder, his gloved fingers digging in painfully as dark energy coursed from his animus into her being. The transition was painful, agonizingly so, but as his strength washed over her body a new sensation began to creep along her forehead. A symbol, similar to the one that the Emperor wore upon his brow, began to take shape from her existing tattoos, the skin reforming itself into a new design.
Once it was over Valeska would feel as if she had been drained of energy, possibly falling to the floor once the Emperor had relinquished his grip. "I have marked you with the symbol of my authority, apprentice. Wear it proudly and know that I accept you as my protege, and will teach you what I know so that you may pass it on to the next generation of Sith Lords."
Several months later...
The training arena was home to the sounds of exertion and the clashing of lightsabers as the Emperor and his apprentice sparred ferociously, their lightsabers left on at full-power as they traded blow after blow with little more than training tunics to protect their vitals. Carnifex held both of his sabers, connected together at the hilt in the form of a saberstaff, in both of his hands as he twirled both blades back and forth to parry and deflect Valeska's strikes.
"Feel the Dark Side flowing through you, apprentice. Let it become the conduit for your anger!"
They conjointly fought in the style of lightsaber combat commonly referred to as Strong Style. It was the Emperor's preferred style as it allowed him to best utilize his immense physical strength and the energizing drug of anger to overpower and dominate his opponents on the battlefield, his blows strong enough to crack armor or shatter bones if blocked by another blade. For now, he held back a small percentage of his lethal strength as to not inadvertently kill his apprentice, but it was still quite a harrowing scene as the Emperor reacted to every attack with an immediate and vicious counterattack.