Super El Niņos, the strongest and most powerful of El Niņos, impact economies, societies, and ecosystems disproportionately. Despite their importance, we do not fully understand how super El Niņos develop their intensity and unique characteristics. Here, combining observational analyses with simple numerical simulations, we suggest that eastern Pacific intensified super El Niņos result from the interaction of an El Niņo and a positive Indian Ocean Dipole. Further, we identify a self-limiting behavior inherent to El Niņo Southern Oscillation (ENSO) dynamics. This behavior?a consequence of the atmospheric Kelvin wave response that develops to the east of ENSO's convective anomalies?dampens sea surface temperature (SST) variations in the eastern Pacific, thereby preventing super El Niņos from developing through tropical Pacific dynamics alone. Our model explains the features of the large 1972, 1982, and 1997 El Niņos; the large SST anomalies during the 2015 El Niņo, however, were likely enhanced by strong decadal variability.