Renderer, not render. As in a rendering engine. Arnold, Redshift, Vray, Corona, Renderman, Octane, and so on. There's no need to stick with just Arnold, if you're using Maya. You can pick the one that best fits your needs. For me Arnold is not viable for example, since I need fast render times, so my animations don't take years to render. For that, unless you have a massive farm at your disposal, your best option is a GPU renderer. While Arnold has some GPU support, it's still extremely limited. Personally I use Redshift. The only thing I use Arnold for, is for previewing my bifrost graphs before caching them to use with RS. Of course, you can buy a lot of those for Blender as well, although some of them are lacking features that they have in other packages.