You can't do that be ause the wave serpent would get prefered enemy if he disembark a guardian squad within firing range, that would be too strong, desactivate the shield fire everything and there is nothing left of the nearby unit. I think it's too strong. Btw do you think if a wave serpent have a guardian unit inside within 12 of an enemy unit, does the other guy get the prefer enemy? I don't think so but what do you guy's think.