I found Ludwig last night. One word about that fight: thrilling.
One piece of the beautifully perfect end run consisting of some of the best boss encounters I've ever had the joy to battle. Utter sublime rapture!
The DLC contains (arguably) the best bosses in the game, with one of the most twisted and fantastic settings as well. Do yourself a favor and find a way back to that tortured place- the destiny of all blood drunk hunters to wander, cursed eternal...I got turned off the DLC because I came to it a while later and I came to it in NG+ and I was getting my ass kicked a lot, especially when I got to the first boss. Made me wish I had made a save before I started NG+, but I didn't have one. Some day I will come back to it and try it with a fresh run but it's really hard to get motivated to do that. I'm sure the DLC is quality though.