Grim Rust vs Balor Brown

How close are they?

ΔE 14.9, fair: the same colour family, but not a straight swap. Balor Brown is more muted, cooler than Grim Rust. They are different kinds of paint: Army Painter Grim Rust is a fluorescent or effect paint and Citadel Balor Brown is an opaque base/layer paint, so they won’t behave the same on the model even where the colour is close.

Can I use Balor Brown instead of Grim Rust?

Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 15). Balor Brown is more muted, cooler than Grim Rust. They are different kinds of paint.

Can I use Grim Rust instead of Balor Brown?

The same difference applies the other way round: Grim Rust is more saturated, warmer.

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.