Brad Dourif fits well with Mundus, for being an embodiment of all evil villains and all.
I mean when Dante meets with Mundus at his office, they'll chat and Brad as Mundus, will give out some traits from his last villain roles... mostly the murdering doll. Dante would shut him up and **** him off to get him away from the Hellgate by chatting up the pain Dante had to endure and how he suffered by Mundus' hands in losing the only family he had. But doesn't mention Vergil.
When Mundus gets angry at Dante's words and throws out a rage and tantrum, he tries to rip out Dante's heart. But when he finds out the Hellgate was broken, he thinks Dante did it as he strangles him. However, unexpectedly, Vergil made it just in time as he slices Mundus and impales him.
As Mundus is bleeding and is in shock of the fact Vergil is Dante's brother, he lets Dante finish him off with three punches, taking out all the pain his life suffered and then throws him off the building, landing him into where blades are tipping up, right at his stomach and face. Also with Dante spitting at him on his way down.