SCP-2845, duh.
The flash becomes a puff of hydrogen, along with everything else that ever existed, instantaneously.
The very instant that 2845 realizes that it isn't contained, he'll -blam!- with everything. I can see it now -- the speedster goes in for a light-speed sucker punch, 2845 is nailed, and a moment later quick guy finds out what it's like to not exist.
English
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Powers? I couldn't find anything on him
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Basically a reality warping deer/God. I see that "no reality warpers" rule now.
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Breaks the rules of the fight honestly. The being can take and transmute any matter into generally metallic-hydrogen/helium compounds just by thought alone.
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