Tauros

Tauros is a bull Pokemon from the Kanto region. It is a Normal type but it is very strong and incredibly vicious. They are not to be trifled with as they are feared and can be very lethal even out of herds. They can be tamed like any Pokemon, especially in herds but it's not an easy feat to accomplish.

In the anime, Ash had caught 30 of them within the Safari Zone, but due to some controversy issues from that episode, it was never shown outside of Japan, so it never reached America, leaving American viewers without knowing how Ash obtained the Tauros.