When you're in Explosive Mode, you'll need to produce multiple explosive punches in a row in order to gain a streak.
Each time you hit a target accurately and fast it will explode with a glowing ring and produce an explosive punch. To get an explosive punch, you'll need to accurately hit a jab or cross at a minimum of 3.3 meters per second (M/S) and hooks and uppercuts at 5.1 M/S. By doing this multiple times in a row, you’ll be rewarded with explosive streaks.
Your highest explosive streak will then be converted to bonus points at the end of each game. This means the harder you work and the higher the streak, the more points you’ll earn at the end of each class.