Clarence could not have been less surprised at the ambush even if he'd seen it coming with hours to prepare.  The arrow flew straight and true with Clarence himself left with a mere fraction of a second to respond.  In that fraction of a second; however, subtle and crucial factors began moving.  First was of course the arrow whose path remained true.  Second, however, was the angry plasma surge of Clarence's Ember Aura which hammered the intruding arrow with several sequential bolts of plasma.  Third, however, was the slow thawing of time itself at the moment the arrow struck his right shoulder as Clarence activated his Time Alter – Red Menace.  

As time once measured in milliseconds now descended into a flow of mere nanoseconds as Clarence took stock of his situation.  His opponent's arrow had burst into a fair approximation of buckshot just prior to impact – and Clarence's own Ember Aura was already pelting it with several plasma bolts as intended.  To this Clarence needed only to add his own Subversion Field – appropriating the heat around him and rapidly freezing the air near the point of impact.  That included his own plasma bolts,  which in the freezing air would become rapidly cooling air breaks hitching a ride on the arrow fragments on their way to impact his shoulder.  Time still flowing nanosecond by nanosecond Clarence focused on facilitating as rapid of a freeze in the area near his shoulder as he could effect.

But even within Time Alter the arrow still came onwards, fractured, and eventually – hit.  But the shoulder armor withstood the hit – pitted and scarred, but intact thanks to its tungsten construction.  Already he could feel the force behind the arrow's energy trying to knock him off his feet despite the effects of Time Alter.  Even if he could somehow avoid that kickback from the arrow's impact Clarence was in no mood to do so.  As the heat around him was being absorbed the smoke began to clear and Clarence could see his enemy.  The velocity of his arrow parting what little grain remained to conceal him.  

As such Clarence immediately switched tacks to Time Alter – Final Black Flash.  Now time once again proceeded micro-by-microsecond... only this time in reverse.  It was Clarence himself speeding up his internal clock.  A certainly painful experience, but a necessary one as the additional time relative to the outside world allowed him to gather up a deluge of Arctic Flames and intensify them.  He pushed his ability to its limits to gather and direct said deluge of Arctic Flame at his opponent.  Under the effect of Final Black Flash – this counter-attack would be launched at speeds in excess of a speeding bullet train the moment Time Alter came to an end.  Which it did immediately thereafter.  

Clarence would suffer a bruising hit to his shoulder and get knocked off his feet and blown back and additional meter or so thanks to the side effects of Final Black Flash.  But in kind – Clarence was able to strike back in the same few seconds with his own torrent of Arctic Flames that rapidly froze everything it touched thanks to its below absolute zero temperature.  And that wave of ice was heading straight for Thomas.