Clockwise from top left: the LOKI, FENRIS, HEL and YMIR mechs.

The RAGNAROK-series Mechanized Forces, also known as the Series-R Security and Protection Arsenal (SPA), was a product family of automated security mechs manufactured by Hahne-Kedar Solutions. Following the Battle of the Citadel in 2183 CE, a massive galaxy-wide revolution in mechanized arsenals took place, with the first mech designed and prototyped by the asari-owned Linekasa Corporation in January 2184 CE, followed closely by the SleepEasy Gen II series by Synthetic Insights, Ltd. and the RAGNAROK-series by Hahne-Kedar's defense subsidiary. Over the course of a year RAGNAROK would dominate this new market, leading to Hahne-Kedar Solutions ceasing production of its other products to focus entirely on mass producing RAGNAROK mechs for dozens, and later hundreds of clients, with RAGNAROK outselling much of its competition by late 2184 CE. The reason for this near total dominance of the market was two things: affordability and its adaptability. The RAGNAROK-series became renowned for producing mechs that could be heavily modified by their prospective clients, offering four easy templates from which a customer could modify to suit unique roles for which the customer purchased the unit for: this meant that each of the four mechs that formed the RAGNAROK family of products could be customized for specific roles that included security, law enforcement, defense, force multiplication and more. Everything from armor to weapons to even its internal programming could be customized, with detailed manuals and programming suites offered in deluxe packages for customers willing to cough up the extra credits. Tens of millions of RAGNAROK units would be built during the product's lifespan, massive factories dedicated to their manufacture built by Hahne-Kedar on numerous worlds to facilitate the mass production of these units, and they would ultimately prove to be Hahne-Kedar's most successful product, with mercenary companies such as Eclipse and even paramilitary organizations such as Cerberus fielding them in massive quantities. As the same suggests, Hahne-Kedar utilized a naming convention for its mechs inspired by the gods of the Norse pantheon.

Four types of mech were sold under the RAGNAROK licensing, each serving to address a particular role while still offering the customizable suite the product was renowned for. The cheapest of these was the LOKI mech, a human-sized bipedal walker with light armor designed for light security and infantry support. The FENRIS mech was modelled after a human dog with the size of a varren, designed for fugitive round-ups, crowd control and disruption of hostile formations. The YMIR mech was by far the product's most expensive offering, representing a heavily armoured, bipedal tank armed with a heavy rotary cannon and missile launcher, designed for prolonged combat situations and infantry support, although the mech could also be stripped of its weapons and used as a heavy duty labor unit. The fourth and final mech was the HEL drone, a small aerial unit armed with twin autoguns designed for patrol work, security and a myriad of other roles that require an air-capable, small automated drone. These four mechs became a staple across the galaxy, and numerous variants would even be developed using the RAGNAROKs as a template, either improving upon the original design or redesigning them for entirely different purposes than was originally intended. The RAMPART mech, for example, was a highly modified LOKI mech developed by Cerberus Skunkworks that possessed thicker armor, reworked servos that allowed more flexible and efficient movement, and a built-in omni-blade suite for close-quarters combat and tech armor for better protection, allowing the mech greater operational and combat utility than the LOKI mech was originally capable of providing.

The RAGNAROK-series mechs saw extensive use throughout numerous conflicts, including the many mercenary and gang wars that plagued by the Terminus Systems and even saw use by the Facinus Liberation Front during the War on Taetrus: several legions of RAGNAROK-series units would be utilized by both sides of the War for Garvug, and hundreds of thousands would be deployed and used extensively throughout the Reaper War. They continued to see use throughout the Border War and the Post-Apocalyptic War, although they were beginning to become obsolete due to the large-scale sweeping advancements in technology. In 2218 CE, Hahne-Kedar unveiled the ASGARD-series, offering four new units that took inspiration from the RAGNAROK-series, but were most importantly ultramodern and more sophisticated than their predecessors. By 2220 CE, the RAGNAROK-series officially ceased production, with all Hahne-Kedar factories heavily retrofitted to accomodate the necessary facilities to manufacture the new ASGARD units. By 2240 CE, very few RAGNAROK-series mechs remained in active service, as it was not only cheaper to simply replace them with ASGARD units, but the parts needed to maintain them were no longer even produced by Hahne-Kedar, therefore making maintenance on the RAGNAROKs far too cost-prohibitive to be worth keeping.