Hecatoncheir

Hecatoncheir (ヘカトンケイル) is an ancient beast and antagonist in Volume 3. Created when the gods first began making pieces for their war games, Hecatoncheir is known for having countless arms and striking down gods of order.

Appearance
Hecatoncheir is a massive creature that sports numerous arms numbering at least a thousand, which belies its title as "the hundred-handed one".

Background
Hecatoncheir is a giant beast created during the age of the gods, affiliated with the gods of chaos.

Goblin Slayer Volume 3
Dark Elf intended on using his cursed artifact to summon Hecatoncheir. When he was forced to confront Goblin Slayer's party the night after the Harvest Festival, Hecatoncheir's power granted Dark Elf five additional arms and the ability to deflect arrows. However, Dark Elf was eventually defeated before Hecatoncheir could be summoned. And in the astral plane, Hecatoncheir was killed by Hero.

Abilities
The numerous arms on its back were able to deflect any arrows coming towards it, something High Elf Archer's grandfather lived to see.
 * Arrow deflection: The sheer amount of arms Hecatoncheir has enables the beast to prevent arrows from hitting it.

Trivia

 * Hecatoncheires (The hundred handed ones) were three giants from Greek Mythology possessing fifty heads and a hundred arms each. The offspring of Uranus (Sky) and Gaia (Earth), they were imprisoned by their father and later freed by Zeus to aid the Olympians in their war to overthrow the Titans.