Groupings of five are what happen when your riff decides that four notes per beat is for cowards and five is a personality. It feels great, it sounds hypnotic, and it will absolutely convince your tapping foot that it has been lied to its entire life.
This little clip is Riff #31 from Morbid Coal's Dante Inferno Suite, and it doubles as a proper rhythm exercise: a five-note cell looped over a steady 4/4 pulse until the accent walks all the way around the bar and comes home. It's short, it's mean, and it's the good kind of confusing.
How groupings of five actually work
Here's the whole trick: a bar of 4/4 holds sixteen sixteenth notes, and sixteen doesn't divide by five. So when you take a five-note pattern and just keep repeating it, the start of the cell lands on a different sixteenth every time — beat one, then the "e", then the "and", and so on — until after five repetitions (twenty notes, over five beats' worth of space) everything lines back up. That drift is why it sounds like the riff is rotating against the pulse instead of sitting on it. It's the little sibling of true polymeter, and the exact same math powers the Free Bird polymeter lick.
The concrete takeaway: do not count the fives. Keep your foot stubbornly on the quarter-note pulse (1, 2, 3, 4) and let the five-note cell fall wherever it lands against it. If you try to count "1-2-3-4-5" AND stay in time, your brain picks a lane and it's usually the wrong one — the same trap that makes you lose beat one in a metal rhythm puzzle. Pulse in the foot, pattern in the hands, and let them disagree in peace.
Nail it and you'll feel unstoppable; miss it and you'll rediscover that your foot and your picking hand have never actually met. Want the PDF, the Guitar Pro file, and me counting this out loud like a lunatic? It's all on my Patreon.