Digger

The Digger[1] is an engineering vehicle cut from Half-Life 2 during the later stages of the game's development.

Overview
Apparently a disused engineering vehicle, it can be found in the map "d1_town_02" of the playable Half-Life 2 Beta. Like the Jet Ski or the AirEx Truck, its textures were not finalized at that time. It is unknown if they were.[2]

Use
In that map, the player must use the Digger to proceed to the next area by destroying a creature made of three tied Advisors with a barrel in the middle, constantly laying HeadCrabs in a cave recycled in the retail map "d1_town_04". Those three Advisors are likely a placeholder for a Gonarch set on a Combine Big Momma Pod that was never finalized. The player must reach the Digger through an incomplete, blocky corridor carved into the rock. He was then to go down a long path with wooden posts installed regularly that bar the way, before he kills the Gonarch with the vehicle's dented digging wheels. This task is however impossible to achieve, since if the player gets in the Digger by pressing the "Use" key, he cannot get out of it, nor operate it.

Trivia
Two Digger sounds can still be found in the Half-Life 2 sound files, in the folder "/sound/vehicles/".