Mesh as polygon Colider

I am making a precedural 2d voxel game and i need to be able to take the mesh that is generated and use it as the polygon colider. I tried just asigning the verteces of the mesh to the points of the polygon collider but i get strange slopes. I also tried makingeach tile its own path but that proved too laggy. Is it possible to achieve this? Or should i just use a mesh colider or lots of box colliders?