"Happy?" may not be as diverse as it's bass counterpart, but it still offers Guitarist's with an interesting, yet very chord heavy chart.
The intro to this song gives you a pretty good taste of what the main meat of this song is. A series of steadily strummed single notes, which trail off with a hammer-on note, then segue straight into three-note chords, then some two note chords, and then a funky part right at the end which has you playing a small trill, and hitting some chord hammer-ons. It's a good mix of everything in such a small amount of space, and the small hammer-on break between the chordy parts should give you down-strummers a slight reprieve!
About 40 seconds in, you get this lovely ambient part that has your fingers shifting up and down the fretboard as you play multiple hammer-on strings, with the odd chord thrown in every now and then. This is a good wind-down from the main pattern, and fun to play.
The next section in my opinion, will give less experienced Expert players problems. Your fingers will be darting between chords, then dashing all the way to the other end of the fretboard to hit orange notes in-between. It's an unusual pattern, and it shifts around a lot, but it's rewarding to hit.
It all comes together to make one of the better chord heavy songs in the game in my opinion. Well worth a buy.