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Some humanoid Cylons are also affected by the Shield of Disapproval. So far, the only Colonial immune to the Adama Glare is Doctor Cottle, who is able to scowl intensely himself while making important medical decisions. Helena Cain resisted a Glare once, but the strain resulted in permanent back problems, exacerbated psychotic tendencies, and future vulnerability to the Adama Growled Ultimatum, a much weaker psychological weapon that fails to affect even D'Anna Biers on a later occasion. Other strong opponents such as Kara Thrace have been sent away in tears.
The Cylon are so afraid of the Glare, fearing that resurrected Cylons are too heart-broken to live after being exposed to it, that during the occupation of New Caprica, a treaty between the Cylons and Baltar's government rules the use of the Adama Glare a war crime. Ironically, this prevents the Cylons from developing a Glare of their own, much to the consternation of the Brother Cavil model, who spends the rest of the occupation unsuccessfully pitching new ideas for psychological weapons . Ultimately, Number Five is put in charge of psychological warfare (using the primitive but effective "shout and point guns around" method) , with the Cavil model reassigned to curmudgeonry and social commentary on a full-time basis. At this point, the Cylon occupational force fell back on defenses against psychological warfare. The roving omnipresent eye that distinguishes their military hardware may be a countermeasure against direct contact with the Glare.
The Glare is an innate skill highly dependent upon Adama's personal gravitas—as demonstrated by the fact that officers who rely upon curmudgeonry, drunken curmudgeonry, angst, and chronic angst rather than gravitas never acquire the skill from Adama despite years of close association.
Although Adama never used the Glare in the first Cylon War, he used a similar tactic, namely parachuting down to a Cylon-occupied ice planet looking really pissed off, to force the Cylons to sue for peace. Rather than face the prospect of a young and severely enraged William Adama running around on a Cylon-occupied planet with a crowbar, the Cylons made a hasty retreat with the First Hybrid and signed the Armistice in record time. History may never have adequately recognized Adama's role in ending the first war, had the Cylons not wiped out most of the human race 40 years later, leaving Adama the opportunity to write the first draft of history in his logs.