Metal scales & theory
The theory here is a map of notes you already hear in metal, not a music-school syllabus.
Why most scale practice doesn't stick
If you only know pentatonic box 1, every solo sounds the same. If you memorize seven modes with no riff to play them over, you'll never use them. Connect each shape to the thing metal riffs actually sit on: power chords and minor keys.
Start here
Put the scales to work
Targeting chord tonesWhich notes to land on so solos sound musical.
Lead phrasingSpace, timing and repetition.
Drop tuningsSame shapes, heavier root.
Beginner pathWhen to start learning scales.