You caught a Nidoking!
Nidoking (ニドキング Nidokingu), known as the Drill Pokémon, are a fully grown and developed species of male rabbit, porcupine, gorilla, and rhinoceros-like Pokémon and the final stage in the Nidoran♂ evolutionary line. Its horn is hard enough to pierce a diamond and contains secreted venom, making it a powerful stabbing tool upon prey and Pokémon battle opponents. Nidoking have immense upper-body strength, being able to snap a telephone pole like a dry twig. It uses its tail to smash down its target, then constrict it to break its bones. Its thick tail packs enormously destructive power capable of felling a metal transmission tower. Once a Nidoking goes on a rampage, nothing can be done to stop it. There are far fewer Nidoking than Nidoqueen in the anime. They serve as leaders of herds, with multiple Nidoqueen mates.
In the main Pokémon game series, a Nidoking can only be acquired when a Moon Stone item is applied to a Nidorino. They are the masculine equivalent to Nidoqueen. Nidoking are more primal, fighting other Nidoking for such matters as territory or food (or a Nidoqueen, during mating season). One of the most notable Nidokings in the Pokémon games is the one owned by Giovanni, the leader of Team Rocket in Pokémon Red and Blue, as well as its remakes, FireRed and LeafGreen. However, he did not use his Nidoking until he was battled as the Gym Leader of the Viridian City gym.
In a poll conducted by IGN, it was voted as the 42nd best Pokémon, where the staff commented on how Nidoking does not have a crown. They further stated that “Maybe in Generation VI he’ll finally get the adornments befitting a king”.