It was purple number two

from Danger Doom – No Names Lyrics on Rap Genius

Purple from the food coloring in her Nehi soda. Also might refer to LSD (purple microdot/purple haze)

The food coloring from the soda AND
The LSD (purple haze)

I say this because a couple lines later, DOOM says how she saw the mask and freaked out (maybe she was bad tripping)

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