Hmmm... after watching the first film *gasp* I'm wondering about some of this stuff.
Fire blasts every 1d4 rounds? Gamera fired off 3 in a row when in aerial persuit of the gyaos, which argues for a faster fire rate. Then again, he spent long periods of time not firing them, so the delay mechanic makes sense. However, it's the +58 touch attack that seems really out of place. When fighting the Greater Gyaos (AC 43), almost every fire blast he shot missed. I'd recommend either toning down the attack mod, or increasing the AC of the Gyaos. Plus, a ranged touch attack is just way too accurate for a massive fireball.
On the Amulet of Gamera: The con drain mechanic is great, but I have to argue with the +4 charisma modifier. Did you see that chick? First, she looked better
before she put the thing on, and second, there is no way she had a charisma of 14+ (assuming she started at 10 or 11). Sometimes your taste in women confounds me
[Edit after taking a closer look at Gyaos stats] I'm not so sure about that Sonic Resistance 50, either. Gamera was seriously damaged by the sonic beams the Greater Gyaos fired at him, and if those only do 20d6 of damage, Gamera would have shrugged them off like nothing if he had sonic resistance. While both the Gamera stats and the Gyaos stats are fairly balanced, as monsters to be killed by PCs, the big G has it way too easy if they were to fight each other.