Death Metal vs Orgoth Bronze

How close are they?

ΔE 20.9, loose: different enough that you should pick on purpose. Orgoth Bronze is noticeably lighter, much more saturated than Death Metal.

Can I use Orgoth Bronze instead of Death Metal?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 21). Orgoth Bronze is noticeably lighter, much more saturated than Death Metal.

Can I use Death Metal instead of Orgoth Bronze?

The same difference applies the other way round: Death Metal is noticeably darker, much more muted.

ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.