The Meaning of Strength (強さの意味 Tsuyo-sa no imi) is the fourth episode of Ultraman Ginga S.
The scene first focused on Victorian civilization, where Sho explained to Repi that his reason for not letting the boy go out was for his own safety. At the UPG Live Base, while Hikaru and Tomoya were talking to Taro, three of them were surprised by the sudden appearance of Arisa Sugita and Gouki Matsumoto. To keep Taro's presence a secret, Hikaru disguised Taro as an alarm/watch clock that Tomoya created for him as a gift. Wanting to make sure everything was further secured, he forced both Arisa and Gouki and himself on a routine patrol at the city.
At Exceller's base, Vorst reported the whole event and furiously swearing revenge on the Ultras. Exceller calmed him down and ordered him to take a rest as the bird alien agreed. Interested of Ginga and Victory's grew in strength, he sent One Zero to test their attacks. She agreed, at the same time even assured to have them terminated. While Sho was reviewing back on his Spark Dolls collections so far, he was alarmed by a surfaced Sadola, whom was piloted by One Zero as she challenged the Ultras to fight her. Captain Yoshiaki Jinno ordered the trio patrolling UPG members to rush to the scenery, but as they tried to do so, they realized that Hikaru went out again, much to Arisa's temper. Sho accepted One Zero's challenge and transformed into Victory. One Zero as Sadola cloaked herself to hide himself, then struck Victory with its pincer. He UITrans into both EX Red King Knuckle and Eleking Tail but, both of them mysteriously vanished before he could use either of them. Sadola gained seized this opportunity and beat down Victory until Ultraman Ginga appeared to save him. Both Ginga and Sadola put up a good fight until Sadola starts launching his arms against him. After that, Taro advice him to use his power and he agreed with it, as a result Ginga transformed into his Ultraman Ginga Strium form and quickly defeats Sadola with Ultraman Jack's Ultra Shot. Sho/Victory watched in disbelief with UPG mambers arrived late and Arisa used Gouki as a punching bag to release her anger at Hikaru for abandoning them. Hikaru tried to cheer Sho up by giving him Sadola's Spark Doll but the man refused and gave him a cold shoulder.
Sho talked to his mother and demanded an answer on why he can't use the other Spark Dolls' powers as she explained that he was hesitate in his objectives. Sho quietly watched Repi used his ESP to lift a rock but his powers didn't last long. Sakuya came and motivated the boy to do better afterwards. He met Hikaru at a park, still giving him a cold shoulder as usual. Their conversation ended after an earthquake happened and Gudon/One Zero surfaced, trying to secure the Victorium that Exceller tried to steal. Sho transformed into Ultraman Victory to fight him and even though Gudon had the advantage because he kept using his whip arms to whip Victory, he still kept on fighting but Gudon just kept lashing at him. Repi witnessed this and asked Queen Kisara's permission to go out to give his adopted brother his Spark Dolls. Before Gudon, could finish him, Shepherdon appeared and saved Victory by grabbing his whip arm before Gudon released it and start to fight each other. Shepherdon had the upper hand at first by slapping Gudon with his massive hands but then Gudon knocked him down his with whips. Before Gudon could kill Repi and Arisa, Hikaru Ultlived into Sadola and saved them. After a conversation, Repi threw King Joe Custom's Spark Doll at Sho and he "Ultlance" his right hand into King Joe Launcher and defeated Gudon with a charged blast.
With the battle is over, Hikaru gave Sho his Sadola Spark Doll and went to play soccer with some kids. Sho finally realised what true strength it is as he finally changed his view on humanity. He caught Repi after the boy managed to sneaked out again but instead of scolding him, Sho gave Repi his wafer snack and let him play at the outside.
- Hikaru Raido (礼堂 ヒカル Raidō Hikaru): Takuya Negishi (根岸 拓哉 Negishi Takuya)
- Sho (ショウ Shou): Kiyotaka Uji (宇治 清高 Uji Kiyotaka)
- Arisa Sugita (杉田 アリサ Sugita Arisa): Yukari Taki (滝 裕可里 Taki Yukari)
- Gouki Matsumoto (松本 ゴウキ Matsumoto Gōki): Takahiro Katou (加藤 貴宏 Katō Takahiro)
- Tomoya Ichijouji (一条寺 友也 Ichijōji Tomoya): Takuya Kusakawa (草川 拓弥 Kusakawa Takuya)
- Yoshiaki Jinno (陣野 義昭 Jinno Yoshiaki): Ryuichi Ohura (大浦 龍宇一 Ōura Ryūｉchi)
- Android One Zero (アンドロイド・ワンゼロ Andoroido Wan Zero): Moga Mogami (最上 もが Mogami Moga)
- Repi (レピ ): Hinata Yamada (山田 日向 Yamada Hinata)
- Sakuya (サクヤ ): Rina Koike (小池 里奈 Koike Rina)
- Kamushin (カムシン ): Yôsuke Saitô (斎藤 洋介 Saitô Yôsuke)
- Queen Kisara (キサラ女王 Kisara Joō): Mirai Yamamoto (山本 未來 Yamamoto Mirai)
- Ultraman Taro (ウルトラマンタロウ Urutoraman Tarō Voice): Hiroya Ishimaru (石丸 博也 Ishimaru Hiroya)
- Alien Chibu Exceller (チブル星人・エクセラー Chiburu Seijin Ekusera Voice): Takuya Eguchi (江口 拓也 Eguchi Takuya)
- Alien Chibull Exceller
- Android One Zero
- Alien Guts Vorst
- Ultraman Ginga S Volume 2 features episodes 4-6
- Ultraman Ginga S Blu-Ray Box I features episodes 1-8.