X-Men Apocalypse is probably the most hyped mutant superhero movie by Marvel and the lead antagonist of the film, played by Oscar Isaac, is something that fans are waiting to see. However, the initial trailer of the movie, released by 20th Century Fox, received criticism for using a more human-like voice for the powerful character of Apocalypse, the God of the mutants.

Addressing fans' concerns, the subsequent trailers released have a deeper/darker voice for Isaac's character. Director Bryan Singer, who initially received backlash for experimenting with a more human-like voice for the Egyptian mutant, has finally opened up about the transition in voice.

"[The first X-Men: Apocalypse trailer] was simply Oscar using his normal voice — which is wonderful; his performance is fantastic — but that was never the intention. We just needed those words to govern the first teaser. So people thought, 'Oh, wait, is that going to be his voice during the whole movie?' It's like, no, but to tell the story of the first teaser, we needed the voice, and I hadn't recreated the voice yet," he told IGN.

The director added that his team started using a new technology and were re-recording all of Apocalypse's dialogues as they suffered technical issues while filming.

"What I'm doing is something very unique. It hasn't been done before. We're re-recording his entire performance because the suit's creaky and makes all kinds of noise, you can't really use any of it anyway.

"But I want his performance. So he's being recorded in ADR using a standard Sennheiser microphone, but also with a bass mic to his right cheek and a bass drum mic to his left cheek. These two microphones have the ability to pull the vocal range out of his voice that the human ear cannot hear. And I can take that vocal range that I've now recorded, and I can pull it and use it to augment his voice — and that with a little digital magic can create a voice that's both completely governed by his performance but is not natural," Singer explained.

He also mentioned that the larger-than-life character will have variations in voice in the movie "depending on different moments".

X-Men: Apocalypse premieres in the UK on 18 May. The cast includes James McAvoy, Michael Fassbender, Jennifer Lawrence, Nicholas Hoult, Rose Byrne, Tye Sheridan and Sophie Turner.