Knuckles the Echidna (Light Mobius)

Knuckles is a mobian echidna, and the (later former) Guardian of the Master Emerald. Due to incidents prior to Mobius: 25YL, he is on hostile terms with King Sonic. He is very protective of Lara-Su, sometimes too much so, such as refusing to let her become Guardian. However this is only to protect her from the contant trials and tribulations he had to go through as Guardian.

Prior to Mobius: 25 Years Later
Before the events of M:25 Years Later, Knuckles became Chaos Knuckles once again, and killed Dr. Eggman. After this, he attempted to recreate the world as he saw fit. In order to stop him, Sonic attempted to use an alien device to turn him back to normal. However, Sonic didn't know how to use the device, and while it did turn Knuckles back, it ruined his right eye, which he replaced with a biomechanical eye.

Mobius: 25 Years Later (Unaltered)
During this time, Knuckles and Sonic are downright hostile to each other, though their wives are able to convince them to have a small gathering at the pool. However, Knuckles finds out from Cobar that Mobius is destabilizing, and could cease to exist if something isn't done. Knuckles shares this information with Tails and Sonic, and a solution is reached. It is decided that Sonic and Knuckles would go back in time to save Mobius. Before they go, Knuckles deems Lara-Su the new Guardian. However, the status quo of the timeline is forever changed...

Mobius: 25 Years Later (Altered)
In the altered timeline, Knuckles is King Shadow's brutal enforcer, with seemingly no memories of the original timeline. He arrests Tails, Lara-Su, and the former King Sonic when the Dark Eyes discover that the three plan to overthrow King Shadow. When they are in prison, Knuckles reveals that he remembers the original timeline, and was just waiting for the right time to overthrow the tyranical king. He then sets the three, along with a rather beaten Rotor, free in order to defeat Shadow. When Sonic confronts Shadow, Knuckles leads queen Sally away from the throne room. After Lara-Su defeats Shadow, she walks out on the arm of her proud father, who says "Your mother's going to flip when she finds out you defeated King Shadow".

Five Years Later...
Knuckles is then seen going out with Julie-Su, and leaving Lara-Su to "take care of things". He asks Lara-Su if she's sure she can handle things, to which she confidently replies that she can. Lara-Su then calls the two, giving them her love before she has to hang up to rein in Manik and Sonia again. Knuckles, along with Julie-Su and Lara-Su, attend the celebration of the Five Years of Peace, when they, along with numerous others, sees a missile flying towards the Royal Family, only for it to be destroyed by Silver the Hedgehog. ( SU: #5)