The famous, ultra high stim Darkside Onslaught with added 4g Beta Alanine.

Beta Alanine is the ingredient that's responsible for that itchy, tingly sensation you get from a lot of pre-workouts. Here's how it's said to work. Muscles contain carnosine. Higher levels of carnosine may allow the muscles to perform for longer periods before they become fatigued. Carnosine does this by helping to regulate acid buildup in the muscles, a primary cause of muscle fatigue.