About 1/3rd of the way through. Having a blast zipping around Zeta Halo like an electrified Spider-Man—unfortunately, I don't think the surface has enough easy vehicle paths, which discourages me from running around in vehicles everywhere (which is a shame, because I love the Marines in this game.) There's stuff in the overworld but I think not too _much_ stuff, since I don't want it to take me 40 hours of collectible hunting to artificially inflate the playtime.