Watch: Stephen Lang discusses debating with James Cameron over Quaritch
The 70-year-old star returns to Pandora as evil military man Quaritch — despite the character's death first time around — in Avatar: The Way of Water.
Lang said he relished the opportunity to work with Cameron again, even if the filmmaker works his actors hard on the set.
"He's a hard taskmaster on himself and I think he demands through the example he sets that you bring your A-game," Lang told Yahoo UK.
He added: "Jim is hard on me. I won't speak to how he is with anyone else at all. But he can be hard on me because he knows he can be hard on me because he knows it works for me.
"I can be equally hard back. In the end, if we go nose to nose, I will lose every time. And that's the way it's supposed to be."
The version of Quaritch seen in Avatar: The Way of Water is a "recombinant" — an Avatar body implanted with the memories of the real Quaritch, copied prior to the final battle that led to his death.
Lang said this drove him to "a more complex performance" than the one he delivered back in 2009, and it involved close collaboration and discussion with his director.
He said: "If we get into a debate, he'll say 'I wrote it' and I'll say 'well I am it'. Eventually we come to terms and the truth of the matter is we're in pretty good sync when it comes to who Quaritch is and where Quaritch is going.
"There may be times when we disagree on the particulars. He's always got 'I'm the director' too."
Read more: Matt Damon regrets turning down Avatar role
Lang said he enjoyed getting the opportunity to play a character he knows well, but with a slight twist that challenges the way the character sees the world — as well as his performance.
"He is Quaritch but he's kind of Quaritch-plus — or Quaritch-minus. He's Quaritch redux, but it's different," said Lang.
The star said: "What's added to him is [the Na'vi spiritual force of] Eywa. What's added to him is the way of water. It has become part of his new, improved or reconstituted DNA.
"And that's gonna have all kinds of effects on him that he can't really understand or predict."
Cameron revealed in 2017 that Quaritch is set to be the main villain of all of his planned Avatar sequels, with the franchise currently set to conclude with the fifth movie in 2028.
Avatar: The Way of Water is in cinemas and IMAX from 16 December.
Watch: Trailer for Avatar sequel The Way of Water