“I love London's Crystal Palace! So, I used it as a reference to make my Noble Phantasm. What's wrong with that?”
It is a Bounded Field Noble Phantasm that manifests a great and beautiful palace that demonstrates the power of the french monarchy. it ranks up Marie and her allies' stats. Even if she has lost her royalty, Marie has faith that the country and people she loved will always remain, so she calls forth the Crystal Palace as a symbol of progress and a new era. It shares a name with the Crystal Palace exhibit in London, England. It's not ironic; it just shows how broad Marie's love is.