Whether you know her as Hope, Heather, or Caroline there is one name everyone knows her as: Charmcaster! Studying under her uncle Hex she learned how to use magic and spells. After betraying her uncle and gaining a rivalry with Gwen she would become one of the Tennyson's deadliest baddies. That said, she has done some things that make her morals more grey (such as when she tried to save her father and even people in Ledgerdomain).
Kari played Charmcaster since the beginning of the franchise and I have issues across the Ben 10 franchise and how the tone can really go all over the place depending on the series, it at least gave Kari a show of range. She could be soft, sinister, calculating, quirky and so much more. I don't want to gush too much since it is no secret that I'm a big fan of Kari so I will just say that I enjoyed her many performances as Charmcaster.
Tara takes over the...magic...mic...sho-Tara takes over the role for the reboot and she doesn't do a bad job...but she also doesn't do anything great. The voice is basic and even when she yells it sounds kinda weak. A shame cause Tara is no stranger to goth magic girls so that fact that she seems so generic is pretty underwhelming. A safe casting call and a decent performance but disapointed that the show that gave us Yuri as Vilgax didn't give us something just as memorable here.