Design pattern

Design patterns, commonly known simply as patterns, are a system of design templates used by the Covenant and its remnants. Design patterns are an integral result of the use of Assembly Forges for materiel construction.

Overview
A design pattern is a specific manufacturing template used to program an assembly forge with the appropriate instructions on how to create a given piece of equipment. Materiel created via this system incorporates a huge swath of designs, ranging from the smallest infantry-portable weapons to the largest supercarriers. Assembly forges then use the instructions fed into them by the design pattern template to direct the actions of nanomachines, allowing them to "grow" subassemblies and integrate various pre-manufactured components into one overall piece of equipment - a process partially-responsible for the Covenant's distinctive curvilinear-organic design stylings.

While useful for manufacturing, the design pattern system does have limitations and downsides especially for a society that restricts the usage of artificial intelligence; they are extremely cumbersome to make and modify, and their use in manufacturing can be subject to mutations and unpredictable errors in design replication. In addition, the materials fed into the template can have a drastic effect on the end product, with design pattern manufacturing being extremely sensitive to variations in input materiel. This can lead to wild and unintended variation in the end products of assembly forge manufacturing; for example, the diminutive was originally created as an accidental - but stable - mutation of the much larger and more standardised  and s. This mutation led to the creation of a ship several times smaller than its intended size, though retaining almost identical proportions.

The creation of design patterns is an art handled by (predominantly-Sangheili) tradesmen known as artisans, and their various specialties such as artisan-armorers and artisan-engineers. New patterns are the result of dedicated labour, with each artisan building upon the work of their forebears, with design pattern lineages stretching back to the eras of Sangheili colonial expansion prior to the founding of the Covenant. The careful study and refinement of Forerunner relics is also employed in the creation of new patterns, a process undertaken by Sangheili and San'Shyuum artificers.

The Jiralhanae do not use design patterns in their traditional weapon and equipment designs, instead opting for a system of manufacture based around clan workshops. However, the foundries of the Banished do employ small assembly forges - something that would have been considered heresy in the Covenant era.

Classification
Covenant standardisation and categorisation has historically been a loose affair, especially by the standards of humanity, due to the Covenant's disdain for serial manufacturing techniques. The UNSC and Office of Naval Intelligence could identify dozens or even hundreds of distinct permutations of a given design - such as the veritable Wraith tank - while by Covenant standards they are considered effectively identical. Human forces during the Covenant War categorised many of these design pattern variations under the type classification system, though these classifications were often incorrect. In many cases, the Covenant lacked any clear etymology for various stylings and armament packages for their equipment - instead considering them under a single banner.

Etymology
Patterns have no known consistent standard for naming, save for that their names are typically derived from the Sangheili lingua franca. In some cases, the translated pattern name translates to a general concept (such as the roughly corresponding with the term "fire seed"), while in others the pattern may be named after the given technology's creator or inventor (such as the  being named after its designer Nakada 'Zadum).

Pattern names do not generally denote a specific series; the does not necessarily imply the existence of other Wuzum-pattern vehicles - rather, the pattern names themselves can be considered more comparable to human starship classification. The M'tara in has the same equivalency as the Scholte in. However, similar groupings of vehicles or weapons created by the same manufacturer or intended for similar roles may share similar names with one another, indicating they exist as part of a series. This is perhaps best observed with the roles of the and,  and s - all of which sharing the Xur-suffix on the end of their names. In some cases, this naming may be abbreviated, such as the Dextro Xur-pattern simply being shortened to DX-class. Similar naming schemes can be observed in Lodam Armory's, and ,  and , and  and  drop pods.

Sangheili origins
Assembly forge manufacturing - and thus by extent design patterns - are a technology developed by the Sangheili of The Former Age, prior to the founding of the Covenant, based on attempts to reverse-engineer the assembler vats used by the Forerunners. Ancient Sangheili warships constructed in assembly forges and bearing pattern designations were employed by the Sangheili during the War of Beginnings in 850 BCE, with many later being decommissioned or abandoned. Over time these ancient ships would later be reintroduced into service nearly three millennia later, with many salvaged from the ashes of long-since destroyed assembly forges.

Covenant era
During the reign of the Covenant, the creation of new design patterns was a heavily-bureaucratic process. New designs were subject to intense scrutiny, and attempting to improve, build upon or substantially alter the work of the "gods" was heavily restricted. Attempting to alter hierarch-approved designs could be viewed as blasphemous at best and heretical at worst, as the Covenant tried to enforce strict controls over pattern standardisation to minimise problems. Despite this, the Byzantine politics of the Covenant meant that certain ministerial organisations, or even particularly notable heroes and influential figures of Covenant high society, could commission specific design patterns for their own ends. In one such case, the Ministry of Concert's was able to break a number of the usual pattern approval processes and go to manufacture thanks to a direct (and unorthodox) blessing from the Hierarchs themselves.

In perhaps the most high-profile examples of such meddling, in the Covenant's final years the Prophet of Truth commissioned an armoury's worth of new design patterns in secret to be constructed by the Sacred Promissory. These weapons were intended for the Jiralhanae in the Great Schism, and in many cases - such as their custom-made plasma rifle - contained upgrades that would have been deemed outright heresy were it not for the Hierarch's personal blessing.

Post-Covenant
Following the end of the Human-Covenant War and the Covenant's dissolution into innumerable disparate states, the San'Shyuum-enforced approval processes for design pattern approval no longer exist. As such, Sangheili engineers and architects have been able to freely explore new avenues limited only by the resources they have available. However, the loss of critical installations like High Charity and the ensuing civil war has seen the remaining available assembly forges become an extremely valuable strategic asset. As such, many post-Covenant factions have sought to reintroduce design patterns - including Vestige warships and other armaments like the - which served in conflicts fought centuries or millennia prior to augment their existing stocks.

The colony world of Hesduros has spearheaded this movement, kickstarting a massive arms industry with manufacturers such as the Hearth of Aspero to manufacture massive amounts of materiel for the Covenant remnant group led by Jul 'Mdama. This action has seen a huge increase in the amount of variations in the design of the plasma pistol.