The Definition of Momentum in Relativity Is Different From Mass Time's Vulcity

In relativity, the definition of momentum is different from just mass time's velocity. In order to have conservation before and after some interaction, for example, you have to use gamma mass velocity,. And this is actually the source of a lot of misunderstanding about relative physics. People used to define gamma times mass as this weird relativistic mass. But it doesn't get larger as you approach the speed of light.