"Everyone thinks I'm a man in real life." (17.27)
Art3mis defies expectations that girls are no good at games and can't be geeks in the end by actually being female.
"No one ever looks anything like their avatar." (17.73)
This line is ironically uttered by Art3mis, the one person who looks the most like her avatar out of all of them. Aside from that one thing, she seems pretty comfortable with herself and her appearance.
"Competition brings out the best in me." (9.113)
Art3mis says this line, but it could really apply to just about anyone in the novel. The competition for Halliday's egg is so heated, it puts the pacing into overdrive. If it weren't for all these highly competitive people, the plot wouldn't move nearly as fast.