The three first met in Sonic the Hedgehog (2006) when Silver attacked Sonic for the second time and Shadow got in the way to protect Sonic. While Sonic escaped, Shadow fought Silver and told him that Sonic was in fact not evil.
The three met again at the end of the game, where they turned into their Super forms to defeat Solaris. However, as the events of the game were erased from history, these events never happened.
The three hedgehogs later appeared in the Sonic Rivals series, where they were rivals. Sonic also raced both Shadow and Silver in Sonic Generations, although by the final boss, Shadow and Silver were among Sonic's friends cheering for Sonic and later appeared at Sonic's birthday party at the end of the game. The three were also allies in Sonic Forces.
The three characters also appear as playable characters in the Mario & Sonic spin-off games, where it is possible to make a team consisting of the three along with a fourth character.
In the comics by IDW Publishing, Sonic, Shadow and Silver are all allies. The three were among the many characters fighting Neo Metal Sonic when it had taken over Angel Island. Later, they fought the Zombot outbreak, but in the process, Shadow got turned into one, and fought against Sonic, Silver and Tails. Silver, Tails and Sonic managed to escape, leaving Shadow behind in Sunset City.
Sonadilver is among the most popular polyships in the Sonic fandom, although polyships generally aren't very popular. Sonadilver combines the popular slash ships Sonadow, Sonilver and Shadilver. Fanart of the three is fairly common on DeviantArt.
Even when not shipped romantically, Sonic, Shadow and Silver are a popular trio in fanon. Fanon ideas for Sonic Heroes 2 sometimes feature the three as a team, with a popular fanmade logo design including color schemes of the three characters.
- Shadow/Silver/Sonic tag on AO3
- Sonic/Silver/Shadow on FanFiction.Net
- Silver/Shadow/Sonic the Werehog on FanFiction.Net
- sonadilver stories on Wattpad
- The name Sonadilver has also been used to refer to a fusion of Sonic, Shadow and Silver.
- Sconadilver - the polyship between Sonic, Shadow, Silver and Scourge the Hedgehog
- SonShadSilvAmy - the polyship between Sonic, Shadow, Silver and Amy Rose