We’re in Open D Tuning for this one.
A simple, two chord phrase that gives you some really beautiful voicings that wouldn’t be attainable in standard tuning. At the core is a chromatic/semitone movement between minor and major which I always feel has a certain psychedelic quality, especially if it’s extended to 7th/9th chords.
The final chord you hear is just the 6 open strings (and you shouldn’t feel “lazy” about occasionally making use of this vibrant convenience!).
If you’re playing electric, whack on the distortion and you’ve got that nimble drop D powerchord fingering at your disposal, which makes this tuning a good combo for your more arty, melodic rock and metal.