
Zeus managed to talk to the Cyclopes Brontes, and convinced him to forge powerful weapons for him and his siblings (which would be more powerful than Kronos' Scythe) behind Kampê's back. However, the gods overcame their fear, and were able to sneak in.

Their guardian, Kampê, was the most ferocious and fearsome monster in all of Tartarus, and even Zeus, Poseidon, and Hades initially shuddered with horror when they saw the infernal monster for the first time. All six of them were imprisoned in the maximum-security zone of Tartarus, surrounded by huge bronze walls, and a lava moat, guarded fierce demons. Poseidon's elder brother, Hades, who was very skilled in navigating under the earth, led all of his siblings into Tartarus with the intention of freeing their uncles, the Elder Cyclopes (Arges, Brontes, and Steropes) and the Hekatonkheires (Hundred Handed Ones Cottus, Gyges, and Briares).

Percy Jackson's Greek Gods Forging the Trident
