->"''I named it Gyaos, because of the sound he makes!''"

Produced in 1967, ''Gamera vs. Gyaos'' is one of the more popular entries in the Showa ''Franchise/{{Gamera}}'' series, and it would introduce Gamera's most popular foe, Gyaos. The film was also the last entry to feature a music score by Tadashi Yamauchi, who also scored the first film as well. This film featured the return of Gamera's love of children, and it was the movie where Gamera became a heroic monster instead of a villain, like he was in the previous two entries. Like the first movie, and all succeeding it except ''Gamera vs. Barugon'', ''Gamera vs. Gyaos'' was directed by Noriaki Yuasa, who also helmed the special effects.

Often considered the last really good film of the Showa Gamera series (Though ''Gamera vs. Jiger'' is another contender), ''Gamera vs. Gyaos'', like ''Film/InvasionOfAstroMonster'', was also the beginning of the end for the franchise, as Gamera's love of children would only cause future films, with the possible exception of aforementioned ''Gamera vs. Jiger'', to become increasingly ridiculous and child-oriented. Oddly enough, the films would still be very gory, with monsters bleeding and losing limbs like a carnival of delicious horrors.

For the ''Series/MysteryScienceTheater3000'' episode, see [[Recap/MysteryScienceTheater3000S03E08GameraVsGaos here]].
!!This movie contains examples of the following tropes:
* AdultsAreUseless: Not all of them, but the vast majority, ''especially'' that reporter.
* AssholeVictim: [[spoiler: Okabe]], who leaves Eiichi behind in a crumbling cave and gets eaten by Gyaos.
* AwesomeButImpractical: Gyaos's forked throat allows him to produce sonic beams. Unfortunately for him, this also means that he is physically incapable of turning his head, just as in every live-action ''Batman'' film from 1989 to 2005.
* BreakoutCharacter: Gyaos. Similar to Godzilla and King Ghidorah, Gyaos would become Gamera's ArchEnemy, having major roles as the villain in several films throughout the franchise and in the video game.
* BreathWeapon: Gamera has his flame-thrower, and Gyaos has his sonic beam, which is due to him having a forked throat, causing him to be unable to turn his head.
* FamilyUnfriendlyViolence: Gyaos nearly slices Gamera's right arm off in their first battle; both monsters, Gamera especially, bleed profusely in each encounter; Gyaos slices his own leg off in the second battle; Gyaos eats people on screen, and [[ArsonMurderAndJayWalking Eiichi throws his toys at some angry villagers]].
* FriendToAllChildren: Gamera, and here is where it became really pronounced.
* GiantFlyer: Gamera and Gyaos.
* ImAHumanitarian: Gyaos, although he also eats some cattle (off screen), as evidenced by one distraught farmer's grieving.
* MakeMeWannaShout: Gyaos uses super-sonic beams produced by a special forked throat.
* OurVampiresAreDifferent: For one, ''this'' vampire can shoot ''sonic beams'' out of his mouth, and he definitely does not sparkle in the light, although his head does glow red. And oh yes, [[{{Kaiju}} he's a 100-foot-tall silver lizard]].
* RedHerring: It would seem like Gyaos' inability to turn his head was implying that Gamera would slay him by breaking his neck. Even the sunlight weakness is another reverse ChekhovsGun, since Gamera kills Gyaos by dumping him into a volcano.
* SpellMyNameWithAnS: Gyaos's name has been spelled "Gyaos" and "Gaos", and no official source has really chosen one over the other.
* WeakenedByTheLight: Sunlight and ultraviolet light are harmful to Gyaos, and it causes his flesh to literally shrink.