Mothra's priestesses are skimpy dressed.

The monsters fight continuously through half of the movie, punching, biting, shooting ray beams, etc.

Several fighter jet pilots encounter Mothra and are destroyed by it.

Godzilla attacks and destroys a submarine full of crew members.

A dead giant monster washes up on a beach. It has an open slash wound along its neck, clearly visible in several shots and close-ups.

The Self Defense Force fights Godzilla with tanks, lasers, missiles, etc. They are often promptly destroyed by Godzilla.

Godzilla bites off one of Mothra's legs.

Mechagodzilla's hand transforms into a drill, which is used to drill a hole into the side of Godzilla. This is more graphic than the usual Godzilla-style fighting, as the drill actually penetrates into Godzilla on screen, tearing a hole in him.

Some characters are seen with blood on their faces, or other injuries.

Damns, hells, and one use of "son of a bitch".

One use of s***.

Drinks are being served at a formal party.

Lots of destruction sequences, some of which involve an old man and a child.