Today at CES '08 Bandai-Namco revealed two guest characters that are going to appear in Soul Calibur 4. They are the famous Darth Vader and Yoda from Star Wars.
I can honestly say I am stunned, confused, and unsure about this mix-match. Yea in Soul Calibur 2 they had odd guest characters but this is even more so odd. Just hope they are at least good characters, not some broken added-on-last-minute characters.
Sources: 1Up.com Kotaku