Many pundits have wondered since Return of the Jedi, how did Vader get that scar on the top of his head?
You know the one on the Sebastian Shaw version of Anakin Skywalker?
Je te presente:
Fans have long wondered who did this to Vader.
The scars below Vader's left eye? That's known.
General Obi-Wan Kenobi was the cause of that - when he had the high ground and left Vader for dead, the lava ignited Anakin and the scars were caused as a result.
Vader clearly suffered disfiguring damage as seen in Revenge of the Sith:
And those are the cheek scars seen Vader's Return of the Jedi visage.
But what about the top scars on the head?
Was it Ashoka when she opened up Vader's helmet in the glorious episode of Star Wars Rebels?
NO.
It was not Ashoka, as he opened the right side of Vader's face mask: