The player is contacted by and introduced to Robert Blake, who explains he's the leader of the S'pht and humans at their base on Lh'owon. Blake explains that before Durandal was destroyed, his last instructions were "for us to reactivate a dormant S'pht AI, sealed beneath the surface and reachable only through teleportation."
Blake doesn't give the player any maps to locate the S'pht AI's personality cells but does say he was convinced by Durandal that this AI is the only way to the contact the lost S'pht clan.
The player should begin by heading east towards the 1x health recharger and the Pattern Buffer. They should encounter a .44 Magnum Mega Class and ammo along the way. Near the eastern Pattern Buffer is switch that has to be activated that raises a platform to enable the player to proceed at a later point in the level.
Next, the player should head west to where they will find two switches near the center that create staircases to allow access to additional areas.
Once all the staircases have been raised the player can use the center area to access the northern section of the level. This has small platform-jumping puzzle that leads to two ledges and then another large room with a platform and ledges.
Finally, the player should proceed to the two personality cells at the end which can be activated via switches. Near the personality cells is a terminal with a message from Blake who will teleport the player out.
The majority of the enemies here are F'lickta and S'pht Compilers, along with several Troopers. Just be careful near the beginning, as in the previous level, The Big House all the player's weapons and a majority of their health was taken away.
There are no known secrets on this level.
Marathon 2: Durandal - Level 19: Begging For Mercy Makes Me Angry