In any Guitar Hero/Rock Band/related game? I've managed to do three.
-When You Were Young in Guitar Hero 3. Never even thought of it as one of my stronger songs until one time out of nowhere when I missed one note. Decided that if that was possible, I could 100% it. Took three or four tries, but I finally did it.
-We Got the Beat in Rock Band 2. Did it my first time ever playing the song, I was like "the f***...."
-Twist and Shout in Beatles Rock Band. Pretty much the same story as When You Were Young.
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darkx congratulates SuperNiceDog. Now go find Nice Dad and email Hungry Shark.
Probably the most difficult ones I ever managed were Peace Sells and Panic Attack in RB2, though You Can Still Rock in America wins the award for difficulty based on how many other people had FCed it at the time I FCed it (zero).
EDIT: Nevermind, forgot I FCed Ride the Lightning on expert guitar. THAT'S my best one.
A few, but incredibly easy ones. I just don't have the patience to go through a song over and over, or even go into practice, to get spots in songs i struggle with down.
Some easy ones, yeah. I think I FC'd Closer in GH3 my first time playing it. Something in 80's, too, though I forget what. And a few slightly harder songs, that actually took me a decent amount of time to get down. The only guitar game I spent much time on was GH2, where I got about 10 FCs (and definitely the easiest ones).
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My rivalry with SuperNiceDog turned out a bit one-sided.
I've done a handful in the Rock Band series. Super easy ones. Stuff like "Charline (I'm Right Behind You)" by Stephen and the Colberts and "Doll" by Foo Fighters.
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If you can read this I've momentarily stopped lurking.