The Big Punch is a Tier 2 Kit for Titans appearing in Titanfall. Your Titan's melee attack power is significantly increased, inflicting greater damage than normal, and knocking enemies back further. Note that your titan's melee attack animation will be longer.
Big Punch is unlocked at Pilot Level 41.
Big Punch is a good choice for those players that tend to get into close quarters with their Titans. It is good for both dealing high damage for players that prefer to stick close to the enemy, and at the same time can be used to keep enemies away from those who prefer to stay at long range. On maps like Fracture, keep an eye on your location, as it may be possible to knock enemy Titans off the map.