  Motivated by the construction of H. Endo and Y. Gurtas, changing a positive
relator in Dehn twist generators of the mapping class group by using lantern
substitutions, we show that 4-manifold $K3#2\CPb$ equipped with the genus two
Lefschetz fibration can be rationally blown down along six disjoint copies of
the configuration $C_2$. We compute the Seiberg-Witten invariants of the
resulting symplectic 4-manifold, and show that it is symplectically minimal.
Using our example, we also construct an infinite family of pairwise
non-diffeomorphic irreducible symplectic and non-symplectic 4-manifolds
homeomorphic to $M = 3\CP# (19-k)\CPb$ for $1 \leq k \leq 4$.
