Cloyster is in the Water 3 egg group and Pineco / Forretress are in the Bug egg group. They are compatible partners for your Wimpod to breed with, since they can learn Spikes through level-up and are in the same egg groups as Wimpod.
Put your (FEMALE) Wimpod and male Cloyster/Pineco/Forretress in the Daycare Center together. Eventually, they will produce a Wimpod egg which will have Spikes in its moveset.