Films: Gorgo (1961)
Location: Ocean/Civilized Area
Height/Weight: About the size of London Tower.
Summary: The best mom is the one willing to go through Hell and back to save her young. Ogra might as well be mom of the year if that's the case. Because no one takes her baby for their amusement and gets away with it. Not while there's a city to turn into rubble.
History: Ogra's species was discovered near the Irish Isles when a volcanic eruption caused them to rise from the ocean depths. The first one seen was Gorgo, a very large individual who was little more than a kid in his species' years. Seeing profit, some sly London twats decided to capture the monster for the appropriately named Dorkin circus. Gorgo became a smash hit with the public, but he was not alone. His mother, Ogra, was enraged by her son's capture, and proceeded to smash and demolish her way towards London despite the army and navy's intervention.
Notable Kills: Nothing special.
Final Fate: London is reduced to a glass floor, but eventually Ogra finds Gorgo, and the two peacefully depart for the sea, leaving humanity to pick up their mess.
Powers/Abilities: Nothing except resiliency and size.
Scariness Factor: 4-Both Ogra and Gorgo are large and dangerous to everyone around them (the latter to a lesser extent). They may not be radioactive and such like the monster they're trying to ape, but a giant monster capable of leveling London isn't exactly child's play.
Trivia: -Gorgo managed to get his own short-lived comic series from 1961 to 1965. It got a little crazy, with spaceships and giant people running amok among other things.
-Ogra was originally going to trash southern Australia, but that place was deemed too unrecognizable by the filmmakers.