True Copper vs Evil Forest

How close are they?

ΔE 30.9, loose: different enough that you should pick on purpose. Evil Forest is noticeably darker, cooler than True Copper.

Can I use Evil Forest instead of True Copper?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 31). Evil Forest is noticeably darker, cooler than True Copper.

Can I use True Copper instead of Evil Forest?

The same difference applies the other way round: True Copper is noticeably lighter, 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.