"Ryuu, thank you for everything... Please watch... my final battle!"
Day of Farewell (別れの日 Wakare no Hi) is the twenty-ninth episode of Ultraman Mebius. It is the first part of a two-part arc which includes a team-up between Mirai Hibino/Ultraman Mebius and Ultraman Taro.
Mebius is told by Mother and Father of Ultra to leave earth, and that if he remains he will be killed. Ultraman Taro makes his way to the earth to take Mebius' place.
Mebius is told by Mother and Father of Ultra to leave earth, and that if he remains he will be killed. Ultraman Taro makes his way to the earth to take Mebius's place. The next morning, he gives Teppei, Konomi, Marina, and George good luck charms. Meanwhile, Inpelaizer heads towards Earth. The rest of GUYS wonder if something is going on, and Konomi suspects Mirai may be quitting GUYS.
The next day is Ryuu's day off, and he goes out with Mirai and asks him if he is thinking of quitting GUYS. They are interrupted when the Inpelaizer arrives, undetected by radar. GUYS members in base deploy. The robot begins wreaking havoc and destruction, while Mirai and Ryuu watch. All of GUYS' attacks are shrugged off by the mecha. Mirai tries to sneak up, but Ryuu notices, while George and Marina are hit by a fireball and hurtle towards the Earth.
Revealing his identity to Ryuu, Mirai transforms and catches the crashing plane. He battles the Inpelaizer, but even his beam is useless against its power. Cutting off its arm only gives it a giant blade, making the mecha more powerful. Just as the robot is about to kill Mebius, Taro arrives. He tells Mebius to go back to the Land of Light, and leave earth to him. The young Ultra protests, but soon fades away; Taro then engages Inpelaizer.
Taro manages blows the top of Inpelaizer to pieces, and it vanishes away. Meanwhile, Ryuu searches through the rubble, shouting for Mirai. He finds the Ultra's human body and cradles his head in his lap while the rubble begins to collapse around them.
- Mirai Hibino (ヒビノ・ミライ Hibino Mirai)/Ultraman Mebius (ウルトラマンメビウス Urutoraman Mebiusu , Voice) - Shunji Igarashi (五十嵐 隼士 Igarashi Shunji)
- Ultraman Taro (ウルトラマンタロウ Urutoraman Tarō , Voice) - Hiroya Ishimaru (石丸 博也 Ishimaru Hiroya)
- Ryu Aihara (アイハラ・リュウ Aihara Ryū) - Masaki Nishina (仁科 克基 Nishina Masaki)
- Marina Kazama (カザマ・マリナ Kazama Marina) - Ai Saikawa (斉川 あい Saikawa Ai)
- George Ikaruga (イカルガ・ジョージ Ikaruga Jōji) - Daisuke Watanabe (渡辺 大輔 Watanabe Daisuke)
- Konomi Amagai (アマガイ・コノミ Amagai Konomi) - Misato Hirata (平田 弥里 Hirata Misato)
- Teppei Kuze (クゼ・テッペイ Kuze Teppei) - Kenta Uchino (内野 謙太 Uchino Kenta)
- Shingo Sakomizu (サコミズ・シンゴ Sakomizu Shingo) - Minoru Tanaka (田中 実 Tanaka Minoru)
- Aide Toriyama (トリヤマ補佐官 Toriyama Hosakan) - Kenichi Ishii (石井 愃一 Ishii Kenichi)
- Secretary Aide Maru (マル補佐官秘書 Maru Hosakan Hisho) - Yutaka Maido (まいど 豊 Maido Yutaka)
- Yuki Misaki (ミサキ・ユキ Misaki Yuki) - Saaya Ishikawa (石川 紗彩 Ishikawa Saaya)
- Kazuya Serizawa (セリザワ・カズヤ Serizawa Kazuya) - Shin Ishikawa (石川 真 Ishikawa Shin)
- Ultraman Mebius Volume 8 features episodes 29-32.
- This episode, along with "The Flame of Promise", were later featured in episodes 97-98 of Ultraman Retsuden.