Great Cave Squig

The Great Cave Squig is simply a larger variant of the more common Cave Squig that has grown to such a magnificent size that it has become as large as an Imperial warhorse. The fangs of these beast are as long as swords and their ravenous appetite would often mean they will snap at anything that moves in front of them. Their hides are tough and leathery and their small eyes gleam with an endless desire for meat and carnage. As one might expect, these powerful Squigs are greatly prized by many Night Goblin tribes, however due to their rarity and vicious behavior, they are thankfully rare.

As Great Cave Squigs are ridiculously dangerous to capture, to ride such a beast into battle is considered quite an achievement for even the toughest Night Goblin Warboss. The process of breaking in a Great Cave Squig cost many Night Goblin lives, but once the beast learns to accept a rider, they serve as a more stable mounts than the more smaller and unruly Cave Squig. This allows a rider a free hand to fight in close combat, instead of just hanging on for dear life like those armature Night Goblins who would dare to ride a Cave Squig into combat. When grouped with Squig Hoppers, the Great Cave Squig have been well known to always lead the pack. Although they are costly to maintain, eating over twice their own body weight daily, a Night Goblin Warboss would do almost anything to keep such a magnificent asset in the hands of his tribe.

Source

 * Warhammer Armies: Orcs and Goblins (8th Edition) -- pg 62