Star Wars - Many things in this episode, such as "Space Wars", Dark Laser, his Star Destroyer-like warship, Timmy's Y-wing-like fighter, Dark Laser's ball shaped drone minions, Cosmo's last minute rescue and Wanda's wand turning into a lightsaber, are all homages to Star Wars.
The fact that this episode has a lot of Star Wars references is because Butch Hartman is a huge fan of the movie series.
Dark Laser's position in the comic book and the letter bold changes at the end of the episode.
In one scene, the front cover of the Space Wars comic appears to be backwards.
Although it happened over a phone, it is somewhat strange that Wanda was allowed to speak to Chester when he called Timmy's house. However, it could be possible that as long as Chester or anyone doesn't know Wanda is a fairy, Wanda is allowed to speak to anyone through a phone.
On the title card, Timmy is pressing the wrong button.
At the end, the copy machine was making copies of Cosmo lying on the copy machine's surface and the copies show the front of Cosmo. But since Cosmo was laying down on the copy machine's surface on his back, the copies should have shown his backside not his front.
The right engine of Timmy's spaceship appears to fix itself in one scene.
Although this episode premiered in 2003, it was produced in 2002 according to the credits.