1 2-liter bottle of Diet Mountain Dew. This has a decidedly evil odd yellow glow to it. Diet is necessary so that you don't over sugar people. We tried other sodas, including Squirt, 7-up and Sprite, but none had that evil yellowness.
4-5 2-liter bottles of a fluorescent blue liquid. The raspberry "Little Hugs" drink for kids are the perfect color. There is a recent Kool-Aid blue flavor that should work well, too.
Mix the two ingredients, together. Adjust the ration as you see fit. You know you've got it right when you get the sickly yellow-green of many Glycol-based Antifreezes. Plus, when you drink, it fizzes!
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