No matter what he did later, Artha going back for Lance in the pilot was awesome
Lance's speech to Moordryd in the episode Wraith Booster, since it contributed to Moordryd taking out the brainwashed Dragon Booster later.
And how does Moordryd do it? By breaking Word's camera, so his father doesn't know it's him saving the day (he's still a "Well Done, Son" Guy after all), and then using rappel gear, not a weapon (well, he dropped his fast), and letting himself be grabbed so he can attach the line. And when that stops working, he pulls a "I Know You're in There Somewhere" Fight speech, despite not knowing who the Dragon Booster really is, and IT WORKS.
Using the line Lance fed him: "RELEASE THE DRAGON!"
Cain growing a backbone in Cain's Mutiny, after taking all of Moordryd's crap he just wants the guy to acknowledge it. The guy splits off and temporarily forms a new crew in opposition to Moordryd.
Rivett, coming out on top in The Mechanist, and no one knowing that he did.
Moordryd in the finale, clearly breaking from his father, and refusing to beat Artha (who he knows is the Dragon Booster) by cheating (his usual modus operendi). And then, when his father tries to cheat against the injured Artha anyways, what does Moordryd do? He stands between Artha and a wraith dragon, knowing he'll get hurt, and mends a fence or two in he process.
Becomes a bit of a "What the hell" for the officials when sure, some of the other Wraith attacks during the game could be made to look like they were accidents Artha had, but Moordryd getting knocked aside out of nowhere in the middle of the field with nothing visible nearby didn't raise a flag?