Sculptris OBJ into UE4?

Blender can export to .fbx, never used Unreal, so I can't guarantee it will work perfectly, but it's worth a shot. If you have access to it I would encourage taking the time to learn Zbrush, the zclassroom series of videos on the pixologic site is a great way to start. It's a lot like Sculptris, but much more varied in terms of brush options and it has great topology tools like Zremesher and Decimation master to simplify the process of turning a high-poly model into something with good edgeflow and a polygon count that will be usable in a game engine. It also has UV master for automating the UV-unwrapping process, it takes some tweaking to get UVs that are as good as the ones a skilled texturer could create manually, but for a quick and dirty texture map you can mess around with in photoshop, it generally does a decent job. Don't mind to come off as Zbrush PR, but outside of Blender, which I use for creating low-poly base meshes, Zbrush is the only tool I use for modeling and I think it's one of the best.