There are two kinds of guitarists: the ones who claim they never learned "Knockin' on Heaven's Door," and liars. This is the song that lives at every campfire, waiting in the dark, ready to be strummed slightly out of tune by someone who insists on doing the Slash solo without knowing a single note of it.
This clip is the slow-burning intro in the Guns N' Roses style, and the beautiful news is that Bob Dylan built the whole thing out of four chords a toddler could name: G, D, Am and C. That's it. If you can spell "GDAmC," you can technically play a stadium anthem.
How this four-chord loop works
Everything lives in G major, so there are no evil borrowed chords hiding in the bushes: G is the I, D is the V, Am is the ii and C is the IV. The whole song is one loop, G–D–Am … G–D–C, over and over, and that repetition is a feature, not a bug: it's why a hundred strangers can join in by the second chorus. The trap almost every beginner falls into is the rhythm, not the chords. In the first bar, G and D each get only two beats, so you switch mid-bar; then Am gets a whole lazy bar to itself. Nail that split and it stops sounding like a chord-change exercise and starts sounding like a song.
Practical takeaway: park a slow metronome at around 60 BPM, count "one-two-three-four" out loud, and change chords exactly on beat three of that first bar. If your chord shapes are shaky, drop the pinky note off C and G and just play the easy grips — nobody at the campfire is auditing your voicings.
And if you catch the Guns N' Roses bug, my Don't Cry breakdown is right next door, still just three chords in a sad trench coat. Get the exact PDF and Guitar Pro files for this one on my Patreon — the Slash solo, sadly, you'll still have to hallucinate yourself.