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V1118 Ori is a classical EXor source whose light curve has been monitoredover the past thirty years (although not continuously). It underwent a powerfuloutburst in 2005, followed by ten years of quiescence and a less intenseoutburst in 2015. In 2019, a new intense brightness increase was observed($\Delta g$ $\sim$ 3 mag). This new accretion episode offers the opportunity tocompare the photometric and spectroscopic properties of different outbursts ofthe same source. This allows one to highlight differences and similaritiesamong different events by removing any possible bias related to the intrinsicproperties of the star-disk system. We discovered the 2019 V1118 Ori outburstby examining the $g$-band light curve acquired by the Zwicky Transient Facilityand followed the decreasing phase with the Rapid Eye Mount telescope in the$griz$ bands. Two near-infrared spectra were also acquired at differentbrightness stages with the Large Binocular Telescope. The last event shows thefollowing characteristics: 1) amplitude similar than in 2015 and lower than in2005; 2) duration less than one year as in previous events; 3) rise (decline)speed of 0.018 (0.031) mag/day, which is different from previous cases; 4) agradual blueing of the [$g-r$] color is observed over time, while the [$r-i$]color remains roughly unchanged; 5) with few exceptions, the near-infraredlines (mainly HI recombination) are the same observed in 2015; 6) the massaccretion rate peaks at Macc $\sim$ 10$^{-7}$ Msun/yr, and decreases in about amonth down to a few 10$^{-8}$ Msun/yr. Our analysis shows that the comparisonof data from different outbursts of the same source is a non-trivial exercise,which allows obtaining important clues useful to drive theoretical effortstowards a better understanding of the EXor phenomenon.

Do subsequent outbursts of the same EXor source present similar features?