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We present a thorough study of the Changing-Look Active Galactic Nucleus(CL-AGN) Mrk 1018, utilizing an extensive dataset spanning optical, UV, andX-ray spectro-photometric data from 2005 to 2019. We analysed X-ray spectra andbroad-band photometry, and performed optical-to-X-ray spectral energydistribution (SED) fitting to comprehend the observed changing-look behaviour.We found that over the 14 years in analysis, significant changes in X-rayspectra occurred, as the hardness ratio increases by a factor of ~2. Wevalidated also the broad-band dimming, with optical, UV, and X-ray luminositiesdecreasing by factors of >7, >24 and ~9, respectively. These dims areattributed to the declining UV emission. We described the X-ray spectra with atwo-Comptonization model, revealing a consistent hot comptonizing medium but acooling warm component. This cooling, linked to the weakening of the magneticfields in the accretion disk, explains the UV dimming. We propose that theweakening is caused by the formation of a jet, in turn originated from thechange of state of the inner accretion flow. Our optical-to-X-ray SED fittingsupports this conclusion, as the normalised accretion rate is super-critical($\mu=$0.06>0.02) in the bright state and sub-critical ($\mu=$0.01<0.02) in thefaint state. Instabilities arising at the interface of the state-transition areable to reduce the viscous timescale to the observed ~10 years of Mrk 1018variability. We explored a possible triggering mechanism for this statetransition, involving gaseous clouds pushed onto the AGN sub-pc regions by arecent merging event or by cold chaotic accretion. This scenario, if validatedby future simulations, could enhance our understanding of CL-AGN and raisesquestions about an accretion rate of ~0.02, coupled with minor disturbances inthe accretion disk, being the primary factor in the changing-look phenomenon.

Interpreting the long-term variability of the changing-look AGN Mrk 1018