When Voldemort discusses the powers of the Elder Wand with Snape, he mentions his 'usual magic':
"No," said Voldemort. "I have performed my usual magic... I am extraordinary, but this wand... no. It has not revealed the wonders it has promised. I feel no difference between this wand and the one I procured from Ollivander all those years ago."
Harry Potter and the Deathly Hallows, Chapter 32, The Elder Wand; emphasis added
What magic could this be?
Clearly he didn't make another Horcrux (he had no need to at this point) and I don't think I noticed him killing anyone, nor making magical arms that strangle people.