Chimera

The Chimera is world object in the Fallout 3 add-on Operation: Anchorage.

Gameplay
The vehicle is a mining rig that has been modified into an armored vehicle. Thomas Morgan explains that the Chinese forces have fitted the vehicle with multiple weapons and reinforced the exterior.

The player character may encounter Chimera tanks twice throughout the campaign, a pair off in the distance during The Guns of Anchorage and at the fuel depot during Paving the Way. Only one chimera is fought, the event taking place at the fuel depot. Walking into a Chimera while crouching will knock the player character down, causing damage.

Appearances
Chimera tanks appear in the Fallout 3 add-on Operation: Anchorage.

Behind the scenes
A cut reconstructed audio log mentions the tanks, the voice line stating, "Chimera Tanks? Come on, man, even you have to admit these are sheer fantasy."

Bugs
The tanks may not be hostile towards the player when first encountered.