Herself:
--Physically, she's incredibly strong. Without using her magic, she's capable of fending off entire platoons of armored, professional knights with nothing but herself and her scythe. She's very proficient with her magic, most of which revolve around fire, seduction, or both.
Magic and Items
--Phoenix: Her scythe imbued with fire itself. It's incredibly large--the blade is larger than she is--but she wields it with one hand easily.
--Fire Lapistier: Her most powerful possession. It amplifies her magic by several fold. With it, she can easily level cities with her spells.
--Flame: Basketball-sized fireballs.
--Heatwave: Fireballs of about ten feet in radius.
--Hellfire: Fireballs about twenty feet in radius.
--Seduce: Uses magic to charm and seduce others.
--Flare Blade: Encases her scythe with magic fire.
--Queen Blade: Allows her scythe to fire molten waves of magic.
--Mega Phoenix: Creates an enormous phoenix made of fire to strike foes.
--Other: Vanessa seems to have various other spells and abilities, such as teleportation, forcibly bringing out others' latent power, and likely typical witch-related abilities.