Stupidity: When Christine is told that to remove the curse, all she had to do was give an envelope with the button inside to somebody else and that individual would go to hell. She decides to go to the cemetery where Ganush is buried and places an envelope into her mouth. Had Christine actually bothered to check inside the envelope first to see if the button was inside, she would never have gone to hell.
Stupidity: Having become the leader of the universe's most stealthy fighters, he promptly leads them in a Custer-esque noisy frontal charge into a force with known weapon and technology superiority. Zero effort to utilize ANY of their amazing stealth, just have them slaughtered so badly that the planet has to sacrifice animals to save them from extinction.
Stupidity: The first time they go into Butler's garage next to the prison they are breaking in, but Butler never witnessed any break in clues to raise his suspicion. They replaced the lock with the exact same lock. It is clear that they didn't know that this was his access point to the prison, but once they found out there is no way to cover up that someone compromised the facility. How is Gerald sure that the bomb will remain under the meeting room while on his way back to the cell? He has a camera in the meeting room but in the bomb room he didn't bother to put one.