ARENA 01:
[Honma Meiko] Gasai Yuno
ARENA 02:
[Gokō Ruri (Kuroneko)] Victorique de Blois
ARENA 03: Tōwa Erio
[Kirishima Shōko]
ARENA 04:
[Kuroi Mato] Eucliwood Hellscythe
ARENA 05: Tachibana Kanade
[Kōsaka Kirino]
ARENA 06:
[Nakamura Yuri] Shiomiya Shiori
ARENA 07: Yuzuriha Inori
[Irisviel von Einzbern]
ARENA 08: Himeji Mizuki
[Kanzaki H. Aria]
ARENA 09: Kashiwazaki Sena
[Akemi Homura]
ARENA 10:
[Nakagawa Kanon] Iwasawa Masami
ARENA 11:
[Suzutsuki Kanade] Shimada Minami
ARENA 12: Fear Kubrick
[Aragaki Ayase]
ARENA 13: Konoe Subaru
[Sakura Kyōko]
ARENA 14: Charlotte Dunois
[Yui]
ARENA 15: Haruna
[Haqua du Lot Herminium]
ARENA 16: Hasegawa Kobato
[Kasugano Sora]
ARENA 17:
[Mine Riko] Elucia de Lute Ima
ARENA 18:
[Mikazuki Yozora] Makise Kurisu
ARENA 19: Tsuchimikado Maika, Shinōji Matsurika
[Harukaze Chiharu, Angelina Nanatsu Sewell]
ARENA 20:
[Shirai Kuroko] Hecate
ARENA 21: Misaka Mikoto
[Sengoku Nadeko]
ARENA 22: Louise Valličre
[Abstained] Ikaros
ARENA 23: Senjōgahara Hitagi
[Nakano Azusa]
ARENA 24:
[Shana] Saber
ARENA 25: Tōsaka Rin
[Holo]
ARENA 26: Oshino Shinobu
[Sakagami Tomoyo]
ARENA 27:
[C.C.] Hirasawa Yui
ARENA 28: Katsura Hinagiku
[Aisaka Taiga]
ARENA 29: Index L. Prohibitorum
[Izumi Konata]
ARENA 30: Kotobuki Tsumugi
[Ichinose Kotomi]
ARENA 31:
[Konjiki no Yami] Sanzen'in Nagi
ARENA 32: Furukawa Nagisa
[Hirasawa Ui]
ARENA 33: Akiyama Mio
[Suzumiya Haruhi]
ARENA 34: Nymph
[Fujibayashi Kyō]
ARENA 35: Nagato Yuki
[Shiina Mafuyu]
ARENA 36: Asahina Mikuru
[Hiiragi Kagami]
ARENA 37:
[Last Order] Illyasviel von Einzbern
ARENA 38: Hinata Hideki, Yui
[Okazaki Tomoya, Furukawa Nagisa]
Few minor tough choices(Kurisu/Yozura, and Azusa/Hitagi), but 38 was by the toughest debated it for a while
.