Why is Marcus the dark horse?

[Jarvio]

Ok don't laugh, I still haven't clocked on why Marcus is referred to widely as the dark horse. Can someone please tell me?

[Staceee]

He is the self proclaimed 'Irrepressible Dark Horse'

[santaa]

He calls himself the irrepressible dark horse

[Jarvio]

Thanks for the info. Why does he call himself that?

[arista]

He reads SciFi Comics
he is in another World .

[BB22]

Marcus' "Irrepressible Dark Horse" dialogue with Big Brother in the Diary Room is one of the best moments of the series. You simply have to see it.