I came up with like a dozen different responses to this news...
1.) As expected of many washed-up celebrities, Darth Vader and Yoda have both fallen on hard times after the trilogies, and begrudgingly appear in soft-core pornography.
2.) Now, whenever Nightmare needs to say something, we will NOT hear "Offer your soul". He too will be redubbed with random soundbites from innocuous past James Earl Jones movies. This will make those endless Guard Impact between him and Vader even sillier. "Ah-HAH!" "Ah-HAH!" "Ah-HAH!" "Ah-HAH!" "Ah-HAH!" "Ah-HAH!"
3.) NO. No. FUCK no. No I won't allow this. NO. this is a dream this is just a dream a bad dream I wanna wake up...
4.) It's still better than Necrid. No, wait. No, it isn't. Necrid was a character specifically made (however poorly) for the SoulCalibur universe. Never mind.
5.) Somewhere in the world you know- you know that the Dark Lord Of The Sith and galactic scourge Darth Vader is going to get his ASS handed to him in triplicate by a 15-year-old Wind Goddess acolyte with big Disney eyes who says things like "You did your best. I respect that."
6.) Voldo will speak for the first time when he slithers up to Luke and Leia and tells them they're creepy.
7.) I'm not going to buy this game out of fear of Cookie Monster walking by the house when I'm trying to (sigh) win the game with Yoda. Once Cookie hears the grunts of Yoda in battle, he's going to think his pal Grover is being tortured inside the house, OM NOM NOM NOM his way through my front door, and swallow me whole.
8.) Yoda will suddenly think he's been transported back to his swamp planet when Astaroth accidentally sits on the Jedi Master.
9.) Okay, so the "long, long time ago" was actually circa 16th Century; fine. But WTF- your idea of a "galaxy far, far away" is feudal Japan???
10.) To best adapt to the SoulCalibur world, Yoda's alternate costume will consist of pasties, a thong, armored boots, and a single spiked shoulder pad.
11.) Screw Yoda and Vader- give me a video game where I can beat the living crapola out of George Lucas. First he mucks with characters from my childhood, now this. There's at least three Summon Sufferings out there with his name on them- one for each prequel.
12.) Oh. Vader just sliced Soul Edge in half. Huh. Well, up until then it was a great video game franchise.