In order to effectively simulate magnetization processes of ferromagnetic materials, it is necessary to use the disorder-based cluster MC method that we also consider appropriate for multi-phase magnetic systems. This approach is based on the Wolff clusterization technique [17] applied to a spin continuous system (described in detail in [22]). Here we present only a general idea based on modification of the so-called adding probability (adding a spin to a cluster) by an additional factor attributed to a local configuration (information) entropy of the selected system’s property (the magnetic anisotropy in our case). Finally, the adding probability takes the form (2) Pijadd=(1−exp(−EijcouplingkBT))exp(−αSiloc) where Eijcoupling is the direct exchange coupling energy between the spins attributed to nodes i and j, Siloc is the local configuration entropy of anisotropy (calculated in the defined sphere around the i-th node) and α is the factor responsible for strengthening and weakening of the entropy impact on the adding probability.