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This is the final photometric study of TW Hya based on new MOST satelliteobservations. During 2014 and 2017 the light curves showed stable 3.75 and 3.69d quasi-periodic oscillations, respectively. Both values appear to be closelyrelated with the stellar rotation period, as they might be created by changingvisibility of a hot-spot formed near the magnetic pole directed towards theobserver. These major light variations were superimposed on a chaotic,flaring-type activity caused by hot-spots resulting from unstable accretion - asituation reminiscent of that in 2011, when TW Hya showed signs of a moderatelystable accretion state. In 2015 only drifting quasi-periods were observed,similar to those present in 2008-2009 data and typical for magnetised starsaccreting in a strongly unstable regime. A rich set of multi-colour data wasobtained during 2013-2017 with the primary aim to characterize the basicspectral properties of the mysterious occultations in TW Hya. Although severalpossible occultation-like events were identified, they are not as well definedas in the 2011 MOST data. The new ground-based and MOST data show a dozenpreviously unnoticed flares, as well as small-amplitude, 11 min - 3 hrbrightness variations, associated with 'accretion bursts'. It is not excludedthat the shortest 11-15 min variations could also be caused by thermalinstability oscillations in an accretion shock.

Photometric variability of TW~Hya from seconds to years as seen from space and the ground in 2013-2017