RR: 7.0
The version of this map that I played was not entirely finished, as Black Dragon decided to make a couple of changes (nothing to do with the fact that I was pretty close to level with him...); please note also that it makes use of the all-purpose new textures file tlabcomp, which you can get with some other maps, such as Gladiator Dome; it is so big (2.82MB) that it isn't worth including it with every downloads file.
          Steps to climb, spherical combat chambers, a pit to fall into, platforms to jump up, using the megajump, to get to the power-ups, a pair of useful arenas at opposite ends... definitely a useful type of deathmatch environment.  The first version, plain Nuts, needed health, a way out of the pit (either by elevator or death-by-lava) and another respawning point or two, but it was well on the way to being a fun place to fight in - this version has changed the spawning place from one of the ends to inside one of the spherical side-chambers, and, obviously, brought in nice bubbling hot lava, so your trip to the pit is fairly brief.  Actually, I found it very hard to get out of the side-sphere and make a clean jump onto the platform; somehow the edge obstructed me, meaning I fell in the lava more often than not...
          Anyway, minor changes; which version you prefer is up to you, and one certainly can't separate them on Reaper Rating.