Plot hole: Clark is crippled throughout much of the episode due to there being kryptonite in the tunnels. At one point he gets a rock stuck in his arm and he bleeds from this wound. For much of the time after this he has blood running down his arm from this wound. After he gets out of the tunnel he is healed but the problem is the blood from the wound also disappears. The actual wound should have healed up but the blood from that wound should still be shown staining his arm.
Smallville (2001)
1 plot hole in season 6 - chronological order
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Trivia: Jerry Siegel, the co-creator of the Clark Kent/Superman character worked on a school magazine when he was at Glenville High School, Cleveland. The magazine was called The Torch - the same name of Smallville High's school magazine, edited by Chloe Sullivan and with Clark Kent as an on/off contributor.
Question: Why does Clark keep burning his "S" symbol on the sides of buildings after saving someone? I get him doing it under the influence of red kryptonite, but at this point it just seems like vandalism that Superman would never do. Clark even saw Chloe having to scrub his mark off the wall of Watchtower, which wasn't an easy task. And if it's meant to be a symbol of hope against crime for the people of Metropolis, why burn it into the side of the refinery in Smallville after putting out the fire?