\renewenvironment{figure}{\let\caption\NAT@figcaption}{}
    
\newcommand{\NAT@figcaption}[2][]{\AtEndDocument{%
    \refstepcounter{figure}
    \ifthenelse{\value{figure}=1}{
        \newpage\noindent%
%        \rule{\textwidth}{1pt}
    }{
        \par\vfill
    }
    \sffamily\noindent\textbf{Figure \arabic{figure}}\hspace{1em}#2}
    }