Even though they used the same Godzilla 2000 suit, Godzilla vs Megaguirus is not a sequel to Godzilla 2000. It is another sequel to the 1954 movie, but Godzilla wasn't killed by the oxygen destroyer in this time line.
The bugs called Meganulon first appeared in the 1956 movie, Rodan.
Godzilla must battle an ancient foe after a worm hole opens from test firing a black hole canon.
The movie was like a step backwards in terms of quality of the story. It was very reminiscent to one of the 90's Godzilla movies, which felt lackluster. Even the characters were bland and I couldn't really care about them. One character is motivated by revenge after her commander was killed by Godzilla and the other character is motivated by wooing her with his knowledge in technology and robotics. This movie's version of G-Force called G-Graspers does not role off the tongue very well. I hate to have a dirty mind, but every time I hear "G-Graspers" I always think that it's something sexual. Couldn't they have come up with a better name or just stuck with G-Force?! I understand why there was "G-Force" because they are a military force of anti-Godzilla soldiers, but I can't stand hearing and saying "G-Graspers".
When it comes to monsters that fly, you usually don't see the strings. In this movie, the strings used to make Megaguirus fly is very noticeable especially in the night scene when it first appeared. Megaguirus is an alright monster, but not one of my favorites. It is more of an egotistical nuisance than anything dangerous. When I say egotistical, I mean it likes to taunt Godzilla A LOT. It uses hypersonic waves with its wings to move faster and the stinger is used to drain Godzilla's energy and then shoots it back at him. Eventually, Godzilla figures out Megaguirus's patterns of attacks and slams it to the ground. There is even one scene that's awesome is where Godzilla does a belly flop on to Megaguirus.
Godzilla vs Megaguirus is not worth sitting through the whole movie for. If you want to watch it, just watch the fight instead of the whole movie. Otherwise, just skip it.