My personal favorites of acts of witchcraft on the show:
[spoiler]1.Angelique puts the curse on Barnabas.
2.Before that, she caused him to nearly choke to death.
3.Angelique showing Josette a vision of herself as a vampire after Barnabas has made her his bride.
4.Nicholas turns Angelique's arm into a skeleton.
5.Nicholas taking away Angelique/Cassandra's powers, making her age.
6.Angelique causing Laura to age.
7.Petofi possessing Charity with the spirit of Pansy Faye (talk about blessing-in-disguise...Pansy was more outrageous, fun and likable than the uptight, self-righteous Charity).
8.Gerard/Judah Zachery taking away Angelique's powers for good.[/spoiler]