To get the Firebreath emote your character needs to receive 100 cheers from other characters.
You can change your character expression by typing the following mood emotes:
mood_angry
mood_apprehensive
mood_calm
mood_confused
mood_fearful
mood_happy
mood_mischevious
mood_sad
mood_sleepy
mood_solemn
mood_surprised
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The thing Gwindeth values the most is respect. Use emotes to show her some respect 
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