Tag Team Trial: Part 2 - S1-E11
Stupidity: After Jaden summons EH Tempest, he also activates the field spell Skyscraper. This means that Tempest gains 1000 attack points (going from 2800 to 3800) when it attacks Dark Guardian (whose attack points are 3800). Since Dark Guardian can't be destroyed by battle, Jaden sacrifices a card to keep Tempest on the field. What was Jaden expecting? He already knew about Dark Guardian's effect, and there would've been no life point damage, so this attack wouldn't have benefited him in any way.
Tag Team Trial: Part 2 - S1-E11
Stupidity: After Jaden summons Elemental Hero Sparkman to the field, he also activates the spell card Spark Blaster, which he equips to Sparkman so that it can change any monster on the field in attack mode to defence mode. He decides to switch Gate Guardian to defence mode, however, he could have also switched Defence Wall to attack mode as well. Then he would've been able to have Sparkman attack Defence Wall, and it would have been destroyed since it has 0 attack points.
