Knuckles may have ambushed sonic and punched the Emerald out of him when he arrives on angel island, but that was because Eggy told him that Sonic was an evil hedgehog out to steal the master Emerald. From his pov he was protecting both the island and the Emerald and arguably the world.
Even then he mostly uses traps on Sonic instead of pummeling him into a lifeless jelly with his deadly fists.
Yeah, and if i remember correctly theres even an alternate/early version of the intro where Sonic isn't super when he arrives on angel island and Knuckles doesn't attack or ambush at all, he just stands there and indicates for Sonic to leave.
Cuz Sonic arriving with the chaos emerald confirms exactly what Eggman was saying and it gives knuckles a very short time to react, and the best thing to do is get the chaos emeralds out of the attacking strangers hands, and he doesn't attack after that, he takes the emeralds and leaves.













