With Avengers: Age of Ultron currently in production, director Joss Whedon and producer Kevin Feige recently offered new details to Empire about the villainous Ultron, as well as the addition of new characters such as Quicksilver (Aaron Taylor-Johnson), Scarlet Witch (Elizabeth Olsen) and Vision (Paul Bettany). The director and producer also revealed why the Hulkbuster concept art was teased in the ABC special Marvel Studios: Assembling A Universe, while giving new details about Thanos' casting in Guardians of the Galaxy, more on Ant-Man and why he won't be appearing in Avengers: Age of Ultron and Marvel's showdown with Warner Bros./DC's Batman Vs. Superman.

When asked about the villainous Ultron, played by James Spader, director Joss Whedon revealed that this massive robot will not behave like other cinematic androids.

"I'm having a blast with Ultron. He's not a creature of logic - he's a robot who's genuinely disturbed. We're finding out what makes him menacing and at the same time endearing and funny and strange and unexpected, and everything a robot never is."

Those who saw Captain America: The Winter Soldier got the first glimpse of Quicksilver (Aaron Taylor-Johnson), Scarlet Witch (Elizabeth Olsen) and Baron Von Strucker (Thomas Kretschmann) during an end credits scene. Joss Whedon revealed that these characters were added to give The Avengers more conflict.

"I fiercely dislike the idea of just throwing in more people for the sake of doing that. But last time I had all of Earth's Mightiest Heroes versus one British character actor, and I needed more conflict."

Kevin Feige added that Quicksilver and Scarlet Witch are at odds with The Avengers when we first see them in this sequel.

"They're not very happy with The Avengers. Their powers are not insignificant and they're quite different from what the Avengers have faced before."

In the end credits scene of Captain America: The Winter Soldier, Baron Von Strucker referred to these siblings as the start of the "Age of Miracles." Kevin Feige hinted that the key to Quicksilver and Scarlet Witch's origins is featured in that scene, which could mean Loki's staff.

""I would say that the Age of Miracles, as Strucker says at the end of that tag, could be a part of that, but the key to their origin is in that tag."

Another new addition to the cast is Paul Bettany, who we reported in February will play Vision, after voicing J.A.R.V.I.S. in several of the Marvel movies. Although the actor himself has talked about playing Vision in an interview earlier this month, Kevin Feige wouldn't confirm that Vision is in the movie.

"Paul Bettany as The Vision? You're confusing me with your mind games."

When asked if the theme in this sequel is fathers and sons, and if Vision would get his own body, Kevin Feige had this to say.

"I wouldn't go that far, in terms of it being that direct a theme. Certainly humanity and humanity's place in our world plays a large part of it, but I think Thor's about fathers and sons, more than this. If one were to confirm anything about Paul Bettany and look at the arc and the line of what Paul has done for us, that's pretty unique and cool and exciting and spins right out of stories we've told in the past."

The producer was also asked about the Hulkbuster concept art that was teased in the studio's ABC special Marvel Studios: Assembling A Universe last month. While he wouldn't confirm what movie it will appear in, Kevin Feige did say they deliberately wanted fans to question what that suit is really for.

"That little tease was very intentional on our part. We found it a very compelling image to throw out there. The specifics around it we don't have to do for a while. It's a piece of armour we've wanted to see on screen for a long time, let's put it that way. What is the Hulkbuster suit built for?"

Director Joss Whedon also spoke about shooting in various U.K. locations, which help differentiate the sequel from 2012's Marvel's The Avengers.

"The number of different looks and texture is and moods we're getting from the British locations is stupid awesome, because this, palette-wise, is very different. I'm trying to make a different film. Because why would you make one movie twice? That seems weird."

Before Avengers: Age of Ultron hits theaters next year, fans will be introduced to the Guardians of the Galaxy this August as Phase Two begins to wind down. It has already been confirmed that Thanos will make an appearance in director James Gunn's adventure, but has this villain been cast yet? Here's what Kevin Feige had to say.

"There is an actor. I'm not sure we want to announce it yet."

It's possible the producer is saving that big reveal for Comic-Con in July, just a few weeks before the movie opens in August 1, but that has not been confirmed.

Marvel's Phase Two has been all about sequels thus far, but Kevin Feige revealed that he's excited to debut Guardians of the Galaxy, in a summer full of sequels and reboots.

"Guardians will feel and seem the most separate. But in a summer where people are going to see a lot of sequels, some of which are ours, and a lot of reboots and familiar faces, we were excited about the idea of bringing something new and totally unexpected to the screen."

Looking ahead, just months after Marvel wraps up Phase Two with Avengers: Age of Ultron, Phase Three begins with Ant-Man. While many thought that this character would be appearing in Avengers: Age of Ultron, Kevin Feige revealed why the decision was made to keep him out of the sequel.

"It was two things - a story Edgar (Wright) wanted to tell that we'll see with Michael Douglas and Paul Rudd, and now we're 11 films in, it's looking at the characters we've already introduced who already have the technology and the brains to do...certain things [Laughs]."

The producer is likely referring to Tony Stark, but when asked if Michael Douglas' Hank Pym is the "original Tony Stark," Kevin Feige had this to say.

""He's certainly older. Original Tony Stark? In that he is an inventor and a scientist, but he has a very different demeanor that Tony and a very different ego, even when he was younger."

He also talked about the decision to cast Paul Rudd as Scott Lang.

"Look at that origin of the petty crook who comes into contact with a suit and does his best to make good, and then look at someone like Paul Rudd, who can do slightly unsavoury things like break into people's houses and still be charming and who you root for and whose redemption you will find satisfaction in."

Since Ant-Man was in development long before Iron Man launched Marvel Phase One back in 2008, Kevin Feige had this to say, when asked how much the project has been changed to reflect the current Marvel Cinematic Universe.

"A little bit. Not much. There's been a little bit of connective tissue that wouldn't have been there in in his draft ten years ago. We changed, frankly some of the MCU to accommodate this version of Ant-Man. Knowing what we wanted to do with Edgar and with Ant-Man, going years and years back, helped to dictate what we did with the roster for Avengers the first time. It was a bit of both in terms of his idea for the Ant-Man story influencing the birth of the MCU in the early films leading up to Avengers."

Finally, Kevin Feige addressed the stalemate between Marvel's Captain America 3 and Warner Bros.' Batman Vs. Superman. There are fans who think that it's a sign of confidence that Marvel refuses to budge, although he wouldn't reveal what their current plans are.

"Well, I'm glad people think that way. We had the flag there first. What other people do and where has always been less of our concern. It's about keeping our head down and doing what we would believe would be cool for an audience to see. I wouldn't say that necessarily."