2401 Penitent Tangent

2401 Penitent Tangent is the Monitor of Installation 05, referred to by the UNSC as "Delta" Halo. Although only shown briefly during the encounter with the Flood Gravemind deep in the bowels of Halo, 2401 Penitent Tangent is nearly identical to its brother monitor, 343 Guilty Spark, with the exception that it glows red instead of blue. It appears that this Monitor may have been captured by the Gravemind whilst in combat as it glows dimly and its outer casing appears to be damaged.

One may assume that he has been on Delta Halo for as long as 343 Guilty Spark was on Installation 04 (for about 101,217 local years of the Installation 05 system). However since it orbits a different gas giant in a different solar system the local time span may vary somewhat. As a result of such long term confinement it is assumed that his personality may also exhibit the rampancy that is evident in Guilty Spark.

Biography
The Monitor of Installation 05, 2401 Penitent Tangent spent millennia floating amongst the ring's various climates and structures, guarding, testing, and watching the ring. It is assumed he fulfilled the custodial functions of a Monitor to the best of his abilities.

Each Halo, as well as being a giant weapon, is a research facility designed with Flood study as a purpose. As a result those Flood specimens left after the Forerunner activated the rings remained on the Installations. At some point after the activation of the Halos, an uncontrollable Flood outbreak occurred, forcing the monitor to search for a Reclaimer. The 100,000 Years War as it appears to be known.

Unfortunately, before he could find one, he was captured and held captive by the Gravemind. Without the guidance of a Monitor, versed in methods of Flood control, the Sentinel defenses could only fight to a stalemate. Eventually creating the Sentinel Wall to physically contain the outbreak within a section of Installation 05.

Apparently, 2401 had been in the clutches of the Gravemind for some time, and was overjoyed when he came upon the sight of the captured Master Chief, believing a Reclaimer could finally activate the facility and contain the Flood outbreak. A short argument with a semi-deceased High Prophet of Regret demonstrated that Penitent Tangent employs a great amount of regulation and protocol when it comes to dealing with the threat of the parasite. Gravemind quickly shut them up and pulled them away into the unknown. This Monitor has not been seen since and his whereabouts and status are unknown.

Trivia
The 7 Motif

Also of interest is the fact that Penitent Tangent's number (2401) is 7 to the power of 4 whilst Guilty Spark's number (343) is 7 to the power of 3, as the number 7 is used frequently in Bungie games and mythology. Also, 2+4+0+1 = 7.

Also, one must note that there are seven unique letters in "Penitent Tangent".

In an earlier Bungie series, namely Marathon, names were often found to be sevens. A numerology grid was used as shown: 0 1 2 3 4 5 6 7 8 9 a b c d e f g h i j  k l m n o p q r s t  u v w x y z

Penitent Tangent is thus P e n i t e n t 5+4+3+8+9+4+3+9=45, 4+5=9 T a n g e n t 9+0+3+6+4+3+9=34, 3+4=7

9+7=16, 1+6=7.

In the Marathon: Durandal port to Xbox Live Arcade, there is an achievement called, "Hats off to 819." The text is thus, "The secret of 2401 lies within." This may reference 2401 Penitent Tangent. I have not yet completed this achievement, and thus need help decoding its secrets. 819 divided by 7 is 117.

Backwash
Penitent Tangent also appears in the Multiplayer map 'Backwash', where he hovers around in the air, occasionally talking quietly to himself. He serves no strategic or combat value whatsoever and never ceases movement. Initially, Bungie wanted to use 343 Guilty Spark instead on the map, but testers kept thinking he was a plasma grenade being thrown, so he was immediately changed to Tangent. Nevertheless, the voice remains that of Guilty Spark. They either forgot to change his voice or had no time to do so.

Appearances

 * Halo 2
 * Gravemind Inside Job Cutscene