I laughed so much reading this thread... i just need to imagine those lines in the game... I'm totally glad Bethesda kept themselves to this crazy style... I laugh a lot at ingame lines.. there are many funny and annoying ones, just like in Oblivion... This is something that i would miss from TES games
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Some examples i found funny:
Just after devouring a dragon's soul while some guards were staying around me, they started yelling "I can't believe it! Dragonborn, just like in the legends!" Then i went to talk to one of them and he said "Let me guess, someone stole your Sweetroll?" ... So much for the Dragonborn hype...
Guards also often say "No lollygagging!" .. I didn't care much about it until i found someone in prison who said that he was there because of lollygagging... Ever since then i make sure i don't do lollygagging around guards xD
Also, check out the male Khajiit traders... i can't keep myself from smiling everytime they say "Take a look." They have a pretty funny accent
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Oh and M'aiq the Liar is awesome, i always have to check him out when i'm around there
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The last time he told me this: "Don't try to block when you have two weapons, you will just get confused. Hitting twice is better anyway."
The more simple ones were mentioned already in the thread ^^
Edit: Oh i got another one... In Whiterun there is a guy who i only talked to once and only asked about his family for like half a minute. Ever since then he always greets me by "You were a good friend to me, that means something."