Shamrock Green vs Warp Lightning

How close are they?

ΔE 17.6, loose: different enough that you should pick on purpose. Warp Lightning is noticeably lighter, more muted, warmer than Shamrock Green.

Can I use Warp Lightning instead of Shamrock Green?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 18). Warp Lightning is noticeably lighter, more muted, warmer than Shamrock Green.

Can I use Shamrock Green instead of Warp Lightning?

The same difference applies the other way round: Shamrock Green is noticeably darker, 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.