Who exactly doesRockyicon Sylvester Stallone play inGuardians of the Galaxy Vol.

2(out May 5)?

But when EW recently spoke with the filmmaker, Gunn did tease Stallones role just alittle.

Sylvester Stallone plays a character from the comics whos an important cosmic character, said the director.

He plays an important role in Yondus life.

And with him is Michael Rosenbaum, my old buddy, who was onSmallvillefor many years.

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He was amazing, he really was, said the filmmaker.

It was a bit intimidating, I must admit.

Those were my heroes as a child.

But with Sly, hes stillSly.

He had to come in on his first day and do this incredibly dramatic, intense scene.

It was really one of my greatest moments on the set.

Guardians of the Galaxy Vol.

2hits theaterson May 5.