Killer Biotic Fx® is a proprietary complex that brings together nature’s most potent immune-enhancing compounds. Killer Biotic Fx® features propolis, a natural agent produced by Brazilian killer bees; the time-tested immune-enhancing benefits of mushroom extracts and the immune supporting properties of colostrum. For best results, use Killer Biotic Fx® as part of a full nutritional program that also includes Ultimate Classic® and Ultimate EFA™.