ΔE 16.4, loose: different enough that you should pick on purpose. RLM 83 Dark Green is a little darker, much more muted, warmer than Wizards Orb.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 16). RLM 83 Dark Green is a little darker, much more muted, warmer than Wizards Orb.
The same difference applies the other way round: Wizards Orb is a little lighter, much more saturated, cooler.
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 Wizards Orb on the colour wheel See RLM 83 Dark Green on the colour wheel
All matches: Wizards Orb equivalents · RLM 83 Dark Green equivalents