The presence of tungsten impurities in tokamak plasmas can have an important impact both throughout normal operation of a device and in disruption regime. During normal plasma operation, the tungsten concentration can be kept sufficiently low to avoid strong radiation losses [1]. However, there are records of sudden influx of tungsten impurities, related to dust particles or melted droplets entering the plasma [2, 3]. In such situations, the tungsten concentration can rise suddenly, leading to a disruption on a time scale for which mitigation measures might not be invoked. In this work, a series of numerical simulations were conducted using the DREAM code [4] to assess the risk related to tungsten-induced disruptions. This at first required extending the atomic data used in DREAM, which was done using the ADAS database [5] and modifying existing atomic models to include the mean excitation energy for heavy elements. The goal was to study the dependence of Runaway Electrons (RE) generation on various disruption parameters. A dependence of RE current on tungsten concentration, magnetic perturbation strength and thermal quench duration is presented, along with other sensitivities to modelling choices and additional degrees of freedom, such as the radial variation of tungsten density. The results show that the disruption dynamics depends on the tungsten concentration and magnetic perturbation strength. Issues related to different approaches of the thermal quench definition are presented. We study the effect of the tungsten concentration profile on the current density evolution, and assess the importance of various RE generation mechanisms. We compare predictions with runaway models of different levels of sophistication. The results provide insights into tungsten-induced disruptions, as well as recommendations for future simulations of such events. Acknowledgment This work has been partially funded by the National Science Centre, Poland (NCN) grant HARMONIA 10 no. 2018/30/M/ST2/00799. We gratefully acknowledge Poland’s high-performance computing infrastructure PLGrid (HPC Centers: ACK Cyfronet AGH) for providing computer facilities and support within computational grant no. PLG/2022/015994. This work was funded in part by the Swiss National Science Foundation. This work has been carried out within the framework of the EUROfusion Consortium, funded by the European Union via the Euratom Research and Training Programme (Grant Agreement No 101052200 — EUROfusion). Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Commission. Neither the European Union nor the European Commission can be held responsible for them. This work has been published in the framework of the international project co-financed by the Polish Ministry of Education and Science, as program "PMW", contracts 5235/HEU - EURATOM/2022/2 and 5253/HEU-EURATOM/2022/2. References: [1] T. Pütterich et al, Nucl. Fusion 50, 025012 (2010) [2] B. Lipschultz et al, Nucl. Fusion 52, 12 (2012) [3] V.P. Budaev et al, Nucl. Matr. Energy 12, 418-422 (2017) [4] M. Hoppe et al, Comp. Phys. Comm. 168, 108098 (2021) [5] H. P. Summers, The ADAS User Manual (2004), version 2.6 http://www.adas.ac.uk