For this specific topic I am interested in finding a solution to this:
How can I place an image in a 3 column environment in such a way that it spans over exactly two of those columns. The third column should be filled with regular text. One might think of something similar using figur* and 2 column and just imagine that there would be a third column next to it.
An option would be ending the three-column and placing minipages, but this is not really a solution, is it ^^ The text would be broken and it wouldn't look nice.
This is just an example of a few things I know that are possible with images and multicols so you might have a starting point.
\documentclass[a4paper]{article}
\usepackage{multicol}
\usepackage[demo]{graphicx}
\usepackage{kantlipsum}
\newenvironment{Figure}
{\par\medskip\noindent\minipage{\linewidth}}
{\endminipage\par\medskip}
\begin{document}
\begin{multicols}{3}
\kant[1]
\begin{Figure}
\centering
\includegraphics[width=\linewidth]{foo}
\end{Figure}
\kant[2-3]
\begin{figure*}
\centering
\includegraphics[width=\linewidth]{foo}
\end{figure*}
\kant[4-5]
\end{multicols}
\end{document}