Core Keeper

This requires the larva helm and larva chest, dropped by the The Hive Mother and Ghorm the Devourer. You can farm these bosses by buying either boss summoning idol sold by the Cloaked Merchant (place the mysterious idol dropped by Ghorm the Devourer in any valid house). The Hive Mother is spawned by placing the idol on the boss rune where you originally fought it. Ghorm the Devourer's rune can be found at a a single short path away from the ring it that it travels. Once you have these, equip them both and then find a Big Larva enemy found in the Larva Hive biome and talk to it.

You have to put Larve helmet and Larve chest on. ( You get them from Hivemother, Larvekills or Larve chests) If you equip the gear, just talk to a larve, they dont attack you anymore because of the set bonus.