  We formulate $\mathcal{N}=2$ global supersymmetric Lagrangians of
self-interacting vector multiplets in terms of variant multiplets, whose
non-propagating fields are replaced with gauge three-forms. Setting the
three-forms on-shell results in a dynamical generation of the parameters
entering the scalar potential. As an application, we study how gauge
three-forms may determine the partial breaking of $\mathcal{N}=2$ supersymmetry
and how they affect the low energy effective description.
