As sin did not want this greed to rebel,his made his personality different. Rather than being a thug who wants everytihng,he is a classy gentleman that silently seeks riches. He prefers to end a fight quickly using his full body shield almost instantly.
Aside from the usual regeneration and halted aging,greed posses the ultimate shield. In which he hardes the carbon in his body making his skin almost indestructable. This allows him to use any part of his own body to attack and defend at the same time.