Fairly easy in this round
ARENA 01: Honma Meiko
[Kasugano Sora]
ARENA 02:
[Nakagawa Kanon] Haqua du Lot Herminium
ARENA 03:
[Suzutsuki Kanade] Gasai Yuno
ARENA 04: Yui
[Gokō Ruri (Kuroneko)]
ARENA 05: Himeji Mizuki
[Nakamura Yuri]
ARENA 06:
[Tōwa Erio] Irisviel von Einzbern
ARENA 07:
[Akemi Homura] Kuroi Mato
ARENA 08: Shimada Minami
[Hasegawa Kobato]
ARENA 09:
[Sakura Kyōko] Elucia de Lute Ima
ARENA 10:
[Aragaki Ayase] Mine Riko
ARENA 11: Makise Kurisu
[Shiomiya Shiori]
ARENA 12:
[Fear Kubrick] Iwasawa Masami
ARENA 13:
[Kirishima Shōko] Kanzaki H. Aria
ARENA 14: Mikazuki Yozora
[Yuzuriha Inori]
ARENA 15:
[Tachibana Kanade] Victorique de Blois
ARENA 16:
[Kashiwazaki Sena] Charlotte Dunois
ARENA 17:
[Konoe Subaru] Haruna
ARENA 18: Eucliwood Hellscythe
[Kōsaka Kirino]
ARENA 19: Cossette d'Auvergne, Kagami Kuro
[Ekaterina Kurae, Maaka Anju]
ARENA 20: Shirai Kuroko
[Ichinose Kotomi]
ARENA 21: Konjiki no Yami
[Fujibayashi Kyō]
ARENA 22:
[Kotobuki Tsumugi] Shiina Mafuyu
ARENA 23:
[Saber] Misaka Mikoto
ARENA 24: Ikaros
[Tōsaka Rin]
ARENA 25: Louise Vallière
[Sakagami Tomoyo]
ARENA 26: Aisaka Taiga
[Senjōgahara Hitagi]
ARENA 27:
[Hecate] Nagato Yuki
ARENA 28: Hirasawa Ui
[Hiiragi Kagami]
ARENA 29: Sanzen'in Nagi
[Abstained] Asahina Mikuru
ARENA 30: Illyasviel von Einzbern
[C.C.]
ARENA 31:
[Nymph] Izumi Konata
ARENA 32:
[Holo] Hirasawa Yui
ARENA 33: Last Order
[Oshino Shinobu]
ARENA 34: Shana
[Abstained] Suzumiya Haruhi
ARENA 35:
[Katsura Hinagiku] Akiyama Mio
ARENA 36:
[Furukawa Nagisa] Index L. Prohibitorum
ARENA 37: Nakano Azusa
[Sengoku Nadeko]
ARENA 38: Lelouch Lamperouge, Nunnally Lamperouge
[Hasegawa Kodaka, Hasegawa Kobato]
Still, Katya is my most favorite "Voiced by Hirano Aya" character after all.