Abstract: Gravitational magnification by foreground galaxy clusters has provided us with the rare opportunity to witness star formation taking place in distant galaxies and under conditions that are among the most extreme throughout the Universe. Gravitating gas weighing millions to tens of millions of solar masses collapse into stars within a volume no larger than the distance between the Sun and its nearest stellar neighbor, forming the so-called super star clusters which are thought to be the early-universe progenitors of globular clusters. When studying the spectra of such super star clusters when they are only a few million years old in a highly magnified Cosmic Noon galaxy, we were surprised to uncover unusual nebular properties that are unknown from local star-forming regions and young star clusters(except for one example!): highly pressurized ionized gas within parsecs of the massive stars, heavy nitrogen pollution, and an inhomogeneous gaseous environment that leads to direct escape of ionizing photons and unusual transfer of Lyman alpha photons. These new findings beg a list of intriguing questions: What is the dynamical origin of these unusual nebular signatures? What stars have dumped the nitrogen? How much dense, enriched gas is there, and does it give birth to new stars? Are there other star formation systems as extreme as this in the local Universe, or at Cosmic Dawn? In this talk, I will present our analysis and findings, and reconstruct an underlying physical picture by applying plenty of knowledge about the physics of the interstellar medium