he is a boss of the haunted cave on the tower
Really to get into the castle you have to be on a quest or teleport to a friend in the battle with lord Nightshade
beat lord nightshade foulgaze
Get a banshee from lord nightshade
fight lord nightshade
he is at the end of the hanted cave down by the tower
the end of the haunted cave
Well, once you reach a certain point in the game, Professor Ambrose will call you and give you a quest to defeat Foulgaze. After that you battle Lord Nightshade.
he is in the tower in the hunted cave he is Lord Nightshade
by fighting lord nightshade 2 times
you have to be lvl. 12
its really easy. get the quest to deafeat lord nightshade in stormdrain tower in haunted cave. after you deafeat him, you will get a skull key.then you can go to the nightside, but lord night shade is pretty tough... so good luck!
Beat Lord Nightshade or ask a friend who can go to Nightside to go in there. Then teleport to him or her.