ΔE 17.9, loose: different enough that you should pick on purpose. Viridian Green is a little darker, cooler than Tomb King Tan.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 18). Viridian Green is a little darker, cooler than Tomb King Tan.
The same difference applies the other way round: Tomb King Tan is a little 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.
See Tomb King Tan on the colour wheel See Viridian Green on the colour wheel
All matches: Tomb King Tan equivalents · Viridian Green equivalents