The civil war took a toll on the Federated Suns' 'Mech forces, leaving them strewn across the battlefields throughout Fed Suns space. The losses for the Davion light 'Mechs were horrendous. With the demand for larger and more powerful 'Mechs, manufacturers were forced to reduce production of lighter 'Mechs to meet the demand. Near the end of the war, the light 'Mech numbers in most of Davion's regiments were so denuded that it severely reduced their scouting and reconnaissance capabilities. Force commanders began calling for replacements to meet mission requirements. Recovered BattRoms from many destroyed light 'Mechs, including the Valkyrie, showed that the limited long-range firepower in the design contributed to their destruction. Designers addressed these issues in the Valkyrie by replacing the older engine with Omni's new extra light. Though it reduced the survivability factor, the new engine allowed for additional firepower.
The designers installed Valiant's new Arbalest LRM 15 missile pack used in the Striker Light Tank. Two tons of ammunition for combat endurance and an Artemis IV was mated to launcher. Defiance's ER medium laser was installed for longer range, combining it with a targeting computer to give the new laser the accuracy of the pulse weapon it replaced. The original endo steel was retained, while standard armor was used for ease of repair in the field. The Valkyrie's appearance was altered, separating it from the original models. Finally as with most of the new redesigns, the Valkyrie's head assembly incorporated a full-cockpit ejection system.

Source: Technical Readout Project Phoenix
Armament:
1 ER Medium Laser
1 LRM-15