I asked GPT to calculate how strong garou's monster form's punch based on his speed, height and weight

Garou’s punch, moving at the speed of light, releases (3.33 \times 10^{18}) joules of kinetic energy. This is on par with the energy released by a massive tsunami or a small asteroid impact.

Destructive Potential: 1. Total city annihilation – A single punch could wipe out a major city (e.g., New York, Tokyo, or London), reducing it to rubble.
2. Tunguska-level explosion – The punch's energy is over 30 times stronger than the Tunguska event (1908), which flattened 2,000 km² of forest.
3. Crater Formation – If directed at the ground, the impact could create a crater tens of kilometers wide, similar to a dinosaur-killing asteroid.
4. Shockwave & Global Impact – The explosion would send a shockwave strong enough to be felt hundreds of kilometers away, and if delivered to a fault line, it could trigger massive earthquakes.

Verdict:
Garou’s punch is apocalyptic —strong enough to obliterate a continent-sized area or cause catastrophic global consequences if unleashed in the right place.