At the beginning, both Gawain and Percival show signs of being torn between their duty and sense of right and wrong. This makes perfect sense for these two characters, considering that they're this game's versions of Knuckles and Blaze, respectively, and both are Guardians saddled with important duties. Interestingly, Gawain is the first to question what the knights have been instructed to do. On a side note, he also tried to commit suicide after failing in his duty (losing a fight to Sonic).
In this universe, Sir Lancelot is right-handed, unlike Shadow, who is left-handed. This makes sense since during Medieval Times, left-handed people couldn't become knights, since they were thought to be demons.
In the main continuity, Shadow is made from Black Doom, who is a pretty demonic individual with a final form called "Devil Doom". Maybe Lancelot is trying to hide something...?
Also, it's possible that Sir Lancelot is actually left-handed, but fights right-handed for a few possible reasons. One, as mentioned is that left-handers were considered "demonic" in that era. Alternatively, he's fighting with his off hand to deliberately handicap himself, seeing as he's both Lancelot (who was known to hold back so as to challenge himself), and Shadow (who is famously cocky and believes himself to be superior).
Sonic is shown to be nervous around Nimue, who looks just like Amy, while the obvious joke is Sonic is remembering how his Amy is the ending of the game reveals he was on his way to a date with Amy, so he probably was remembering the date and realized that she was going to be pissed when he finally got back.
It seemed kinda like an Ass Pull that there just happened to be the barrier stones needed to stop Merlina's magic until you realized that Merlin and Merlina both have knowledge of future events and Merlin put them there because he knew that Merlina would be corrupted.
Lancelot is shown to be the most loyal to his king. Now, of course Shadow would be loyal to a Dark Is Evil villain, as he had some degree of loyalty to Black Doom, after all. But, even better is this: Shadow is ridiculously able to be manipulated, brainwashed, and generally otherwise has Undying Loyalty to whichever villain he ends up controlled by, and has a massive ego. Altogether, it makes a good deal of sense he would end up being a knight. -RileyIsCool
In the finale, Sonic fights a hopeless battle against Merlina, to the point where the other knights, who have been watching him from afar, tell him that this goes beyond honor or chivalry, and that fleeing is the only option. Sonic's refusal triggers Caliburn's rebirth as Excalibur. Why? Because by refusing to flee even in a hopeless battle, Sonic proves that he has internalized everything Caliburn has been teaching him over the course of their journey. While it may not be dishonorable or cowardly for a knight to flee in such a situation, Excalibur is the sword of a king. Caliburn believes that a king must go above and beyond for his people, and that someone who is not willing to die for them is not fit to be king.
Why is Sonic chosen by Caliburn to be King Arthur? A couple of reasons.
He was show what true chivalry is. Lancelot was confused getting mercy while Gawain tried to kill himself upon their defeats, which is exact opposite of the chivalric code dictated in the real Arthurian mythos that embraces showing mercy to the defeated and is against suicide. As King Authur, he has to clear up the misconceptions the knights are having, with a few knocks to the head if he has to. King Arthur is a one that leads by example, after all.
On a darker note, he is bringing back Camelot's pre-destined fall by stopping Merlina. Sure, he is going around saving people from an Evil Overlord and doing heroic knightly deeds which supposedly breaks the aesop but it in the grand scheme of things, he is simply saving them so that they will all get killed when Mordred's rebellion happens. As King Arthur, he is making sure his story goes back on the right track, which includes Camelot's tragic end. That's why even after all the good things he has done, he still considers himself a villain as he knows what defeating Merlina does to Camelot in the long term!! Any wonder he ran back to his world after finding out that he is King Arthur?
Sir Gawain almost immediately tries to kill himself after failing his duty, and during the leadup to the fight Sonic points out the two are similarly in personality. We can assume that, even if Sir Gawain's Seppuku-like tendencies aren't unique to the Arthurian universe, it didn't go anywhere in the main one... but it's still an unnerving thought that Knuckles might contemplate killing himself for a similar failure in duty.
