Rock in D (Drop D) — arpeggios
The three chords D5d, G5d and E5d are single-finger barres across the three lowest strings (Drop D tuning, see the dedicated intro sheet): arpeggiating here doesn't mean picking root and fifth across two strings like on a standard power chord, but isolating two specific strings out of the three the finger barres at once, without sounding the third. That's what explains the level 4 rating, the highest of the catalog's three power-chord arpeggio sheets so far: the difficulty is no longer just rhythmic, it becomes mechanical too — hitting exactly two out of three strings that are physically pressed together by the same finger.
Tips
The one-finger barre should stay down on all three strings the whole time: it never decides which strings sound, the picking hand does.
Hit each note with a short, precise pick stroke, avoiding any wide sweep that would catch the neighbouring string.
If an unwanted string rings out, slow down and watch where the pick stroke ends: it's almost always the pick overshooting, not the barre finger moving.