Cartoon describing our proposed scenario to explain the broad-band spectro-photometric variability of Mrk 1018. The initial condition is an optically thick, geometrically thin disk with internal accretion (η), temperature (T_d), and a magnetic field (B_d). A cloud pushed toward the center – the effect of a wet merger or cold chaotic accretion – passes nearby and starts to deposit gas at a given radius (denoted by the vertical dashed lines) at a rate of η_c (panel a). If η_c > η, the region in the disk where the gas from the cloud accretes starts to puff up. The energy produced via viscous friction is no more efficiently released and the temperature T suddenly rises (panel b). When T ≫ T_d, the hot gas is accreted inward at a rate of η_l > η, triggering this instability in the adjacent inner ring (panel c). The energy starts to be released magnetically and the magnetic field (B) in this region decreases. If η_c ≫ η, this process extends to the whole inner accretion flow, making it optically thin and geometrically thick. The energy is released magnetically (E_b), likely in the form of a jet, drastically reducing the temperature of the gas and advecting the material onto the SMBH at a rate of η_a < η (panel d).