Gojira

Gojira is an unused creature found in the Fallout: New Vegas game files. It can only be accessed by console commands.

About
Called simply gecko when summoned, Gojira is its editor ID. It is graphically identical to the fire gecko, but triple the size. It has its own unique embedded fire breath weapon called 'Gojira Flame' (baseid 0011324c), and a staggering 8,000 HP. It will kill any creature if one is placed beside it. The Legendary Deathclaw is always killed if one is placed near it, making it the strongest monster in the game accessible via console commands.

Appearances
Gojira is only found in the game files for Fallout: New Vegas.

Behind the scenes
Gojira is the name of the Japanese movie monster better known to English speakers as Godzilla.