\listfiles
\documentclass[paper=b6,fontsize=11pt,twoside]{scrartcl}
\usepackage{showframe}
\newcommand*\aPage{%
\Huge
\noindent A \hfill B \hfill C
\vfill
\noindent X \hfill Y \hfill Z \newpage}
\usepackage{blowup}
\blowUp{target=a4,pos={inside,top},noscale}
\begin{document}
\aPage
\aPage
\aPage
\aPage
\end{document}
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