  Using combinatorics of Young walls, we give a new realization of arbitrary
level irreducible highest weight crystals $\mathcal{B}(\lambda)$ for quantum
affine algebras of type $A_n^{(1)}$, $B_n^{(1)}$, $C_n^{(1)}$,
$A_{2n-1}^{(2)}$, $A_{2n}^{(2)}$, and $D_{n+1}^{(2)}$. The irreducible highest
weight crystals are realized as the affine crystals consisting of reduced
proper Young walls. The notion of slices and splitting of blocks plays a
crucial role in the constructions of crystal graphs.
