It can be tempting to destroy everything inside a Piglin base for rewards, including the portal that brought the creatures into the Overworld.

Although, if you're low on Prismarine and need to farm for upgrades, hold off on sealing the portal device so that Piglin structures with the rare material can respawn and get destroyed again.

Having a few outposts with open portals can be a boon for gradually earning Prismarine without the need to approach more challenging Piglin groups until you're prepared.