"Don't worry. You'll get to see it right now"
Brando gives his stuff for Grim to carry and then starts stripping down. No cloth would survive this transformation. Once it's done, he begins the process. He had done it enough times before to make the whole thing automatic
First he lets his beast spirit begin to change his mind and body. He was a particularly odd case in that. During points of his life his spirit had been the one of a Tiger, later one of a Lion. And then, they got blended into just one thing. Which is what he reached for
As he crouches, snarling a bit, and draws mass and size from the Nevernever. By the time the whole thing is done, he looks very much like a lion with some faint tiger strips in his torso. Some extra hair around the neck and head that looked like a mane. Yes, he looked like a lion with some extra. That is if lions had almost 14 feet and weighted a thousand pounds.
In his new form, Brando searchs for the door. Things got fun now