It looks like an FPP effect, but it's actually a much elaborated way to use the DYCP effect, commonly in order to "rotate" textscrollers and charset based logos around a hypothetical horizontal axis.
One after one, in the same demo
Double rotating textscrollers in Conversations II part 4.
X-axis rotating logo with overlapped 2-chars DYCP Conversations II part 5.
One of the Five Magics: let the letters do roll in a columns.
Stretcher, DYCP, FPP
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