Wilhelm

Wilhelm is a Hyperion cyborg who serves Handsome Jack, and who nearly defeated the original Vault Hunters after the events of Borderlands. He is one of the bosses in Borderlands 2.

Wilhelm is the first major boss of the game. (Major bosses are indicated by health bars on the HUD instead of above the enemy.) He is mentioned multiple times by the Guardian Angel, with considerable trepidation, before he is fought at the End of the Line. He is partly hyperion robot. With his waist down replaced with what looks like Loaders' legs. From waist up, he's like a Combat Engineer with Construtor's eye. Beside that, he also has mounted shoulder mortar for ranged attacks.

He can drop Logan's Gun on death, a unique orange-rarity variant of the Dart E-Tech handgun.

He can also drop Rolling Thunder on death, a unique orange-rarity grenade mod.

Strategy
Wilhelm has a large amount of health and is well-shielded, though he is unshielded for the first few seconds of the fight. He periodically digistructs Surveyors and Shield Surveyors. He can also throw away nearby train compartments to save the Loaders stuck underneath in order to assist him. The Surveyors and Shield Surveyors should be killed off quickly because they will heal Wilhelm and regenerate his shield.

Wilhelm is a powerful melee combatant and can inflict serious harm if he manages to close distance with the Vault Hunter. Occasionally he will launch himself into the air towards the Vault Hunter's location, and will spin his upper body around in circles, knocking the Vault Hunter back. This is very dangerous as he can knock the Vault Hunters off the map. Otherwise, his primary ranged attack is to launch missiles and grenades in the Vault Hunter's direction.

Wilhelm is largely immune to fire weapons, but his shield can be rapidly depleted with shock weapons. Like most Hyperion robots, he is weak to corrosive damage. Thus, he can be rapidly dispatched by immediately unloading a corrosive weapon on him when he first appears, before his shield generates, and then keeping a safe distance while alternating between shock and corrosive weapons, while picking off Surveyors. He has absolutely no immunity to slag weaponry, which is introduced around the same time he appears; combining a slag weapon with fire from a corrosive one can be used to take him down extremely quickly. The ledge overlooking Terminus Plateau provides a convenient position for a sniper as Wilhelm doesn't go up there.

Trivia

 * Wilhelm has no intro cutscene, despite his status.
 * Defeating Wilhelm unlocks the "Wilhelm Screamed" achievement, a reference to the stock sound recording used in many movies, television shows, and video games.
 * Wilhelm's first appearance is in the mission Whatever Happened to Helena Pierce?, when he is heard murdering a trainful of refugees on their way to Sanctuary under orders from Handsome Jack.