Gray beams enabled the Hexer mech pilots to neutralize enemy warships without inflicting excessive damage to their integrity. This would make it easier to recoup the losses of a battle and plunder larger quantities of intact phasewater.
Gloriana still did not think this change was extreme enough.
"A luminar crystal weapon that can fire gray beams will most definitely increase the versatility and combat effectiveness of the Mark III, but it is not a unique advantage anymore. Death hyper materials are becoming increasingly more prevalent, and most notably appear in greater quantities on past battlefields. I think that more and more mechs will be released that are able to employ similar attacks."