 Japanese title card · “Clash!! Sonic vs Knuckles” | |
| Series | Sonic X (ソニックX), TMS Entertainment |
| Season | Season 1 (2003–2004) |
| Episode | Season 1, episode 5 · no. 5 of 78 |
| English title | “Cracking Knuckles” (4Kids) |
| Japanese title | 激突！！ソニックｖｓナックルズ (Gekitotsu!! Sonikku Bāsazu Nakkuruzu, “Clash!! Sonic vs Knuckles”) |
| First aired (Japan) | 4 May 2003 · TV Tokyo |
| First aired (US) | 4 October 2003 · Fox Box (Fox) |
| Directed by | Keiichirō Furuya |
| Written by | Kiyoko Yoshimura |
| Storyboard | Kazuhide Tomonaga |
| Previous episode | Chaos Emerald Chaos (S01E04) |
| Next episode | Techno-Teacher (S01E06) |
RivalrySonic vs Knuckles
Cracking Knuckles is episode 5 of Season 1 of Sonic X and the 5th of the anime’s 78 episodes. In Japan it is called “Clash!! Sonic vs Knuckles” (激突！！ソニックｖｓナックルズ). It premiered on TV Tokyo on 4 May 2003, and the 4Kids English version followed on Fox Box (Fox) on 4 October 2003. It was directed by Keiichirō Furuya and written by Kiyoko Yoshimura.
Synopsis
Knuckles is miserable on Earth. Guarding the Master Emerald is his life’s work, and every day away from Angel Island gnaws at him. Eggman spots an opening: he claims Sonic set off Chaos Control deliberately and is hanging on to the Emerald because he likes the human world better than home.
Knuckles swallows the lie and challenges Sonic to a showdown in the mountains. The two trade punches and spin attacks across cliffs and falling trees, while Chris, Amy and Tails head off for a picnic at Silver Valley.
The duel is a distraction. Eggman’s robot E-47 traps Chris, Amy and Tails behind glass on the far side of a lake, betting that Sonic won’t cross the water. Sonic simply runs around it, and Knuckles, realising he has been played, punches the Egg Mobile into the sky and smashes the robot apart.
Key Moments
- Eggman manipulates Knuckles into fighting Sonic.
- Eggman uses Sonic’s weakness, water, against him.
- Knuckles teams up with Sonic once he sees through the lie.
Trivia
- The set-up echoes Sonic the Hedgehog 3 (1994), where Robotnik also fools Knuckles into treating Sonic as an enemy.
- Written by Kiyoko Yoshimura, her first script for the series; she later wrote 12 of Season 3’s 26 episodes, more than anyone else.
- On home video: Japanese DVD/VHS volume 1 (Victor Entertainment, 23 July 2003); 4Kids/FUNimation volume 2, The Chaos Factor (1 June 2004); the New World Saga DVD set (2007); and Discotek’s Sonic X Collection 1 (2016) and complete-series Blu-rays.
Watch the Episode
The full 4Kids English episode, uploaded by TMS Entertainment’s official “Anime! on TMS” YouTube channel (checked 6 November 2026).
Part of our Sonic X Season 1 guide. See the Sonic X series page for the cast, theme songs and home video.
Sources: titles, credits and air dates from Wikipedia’s list of Sonic X episodes and Sonic Wiki Zone, cross-checked with each other and with Luke’s original Sonic Scene episode table; synopsis written for Sonic Scene from the episode, Wikipedia’s summary and Sonic Wiki Zone’s plot notes; title card and screenshots via Sonic Wiki Zone, copied to our media library.