The web site lists the "ingredients" as alcohol, caffeine, taurine, citric acid, ginseng and marketing...oh, wait, marketing's not listed.
Never having tasted it, I'd guess you could brew a very pale, low- or un-hopped ale to hit your target ABV (OG around 1.070). At bottling, add caffeine, citric acid and ginseng to taste (I don't think taurine would contribute any kind of flavor).
Not sure if it's carbonated or not, but if so you'd want to add some priming sugar as well.
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