All Tasya's theme songs that I prefer is listed here-

Main theme:
Bull's Eye - nano

Although it's in Japanese, I'll say that there's no way I add this as her theme just because it sounds good. Search the english translation, read it, then read Tasya's bio, and you'll understand why-

Battle theme (main):
Vessel of Stars ~ Casket of Star

It's energetic, awesome, cool and not to mention r o c k -

Yep, that's all I can say about it-

Battle theme (half-HATE/aggresive mode):
Vanishing Dream ~ Lost Dream

Hmm, how would I describe it? It sounds from "intensely" creepy to a chaotic-sounding rock, and it describe how mad Tasya will act if certain situation force her to-

Battle theme (Noire's possession):
Doll Judgment 【Intense Symphonic Metal Cover】

Creepy, intense, and epic. Nuff said-

Battle theme (Undertale universe):
Battle in CHAOS - Renox

Cheerful-sounding, just like Tasya's basic personality. Once again, can't say much-