ΔE 20.5, loose: different enough that you should pick on purpose. Orchid Light is noticeably lighter, much more saturated than Warpfiend Grey.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 20). Orchid Light is noticeably lighter, much more saturated than Warpfiend Grey.
The same difference applies the other way round: Warpfiend Grey 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.
See Warpfiend Grey on the colour wheel See Orchid Light on the colour wheel
All matches: Warpfiend Grey equivalents · Orchid Light equivalents