The penultimate mission to the Earth's surface starts off with a decent ammo collection, as if to atone for the sins of Never Satisfied. Then it takes off into an intense, nearly constant battle throughout the level, featuring some of the toughest fights we've yet seen. There are a LOT of monsters on this level, including quite a few MOAHs and some places where monsters simply stream out at you from an unexplored area. The layouts are more complex and sometimes confusing than we've seen before in general; many rooms are divided into a set of hallways which the player must navigate while drones are free to fly over the walls and attack.
One early trick requires you to stand under a gallows to open a door; there are some desirable items (including a 2x powerup) up here so it's not that confusing. The first set of underground passages contains a secret (see Spoiler Guide for instructions) which purports to explain several of TI's secrets, but if it does it's too cleverly concealed for me :) This terminal is also authored by Cosimo. However, aside from a few magic triggers, this level is very well designed. It's got some very complex architecture, including a room lined with huge pillars, and a realistic multi-story building with windows at one end of the outdoor area.
This level is difficult enough that it caused me my second death in this runthrough (doubly embarrassing considering that I'm playing on Normal); the MOAH encountered in a large hallway shortly after finding the manuscript caught me in his death blast.
The terminals on this level are quite different from the ones we've seen before. We learn the full extent of the information S'bhuth has given Leonardo, including his true name and an explanation of time travel. Leonardo is starting to think about future actions, so the S'pht's involvement on Earth is about to end (and again, one wonders why the fictional authors of TI's books bother to record thoughts like "I must destroy this note").
Of course, we can't forget the major secret on this level: The 3x powerup, another Cosimo terminal, and a teleporter to the secret level Game of Death. This is a very small and basic level, so I'll include it in this post. Based on a Bruce Lee movie and using a very common theme in gameplay design (although rarely used in Marathon because it's so contrived), the player is required to unlock a series of areas containing progressively more powerful monsters, gradually opening the way to the end of the level. This level is populated with normal high-level monsters and powerful "champion" Fighters, as well as 4 super-juggies raining grenades on you. I beat the level quite easily, and with rather more ammo than usual, by leading all the Fighters down into the central arena and leaving them there; they don't seem to know how to use the platforms to get back up on the ledge. It's also important to kill the Juggernauts before making a run for the exit teleporter at the top of the central tower, or they'll knock you off with grenades. This level is the first place outside the Repositories that we've seen health recharger since Polygonium Opus; don't forget to top off your tanks before leaving.
