Watch S02yu-gi-oh: 51

"Fool! Changing it to attack mode only makes it vulnerable, but it still has 2400 defense!"

"Now, the effect of !" the clone sneered. "When it is in defense mode, you cannot activate card effects, and if you attack it, your monster is destroyed!" The crowd gasped. The field was paralyzed.

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Across from him stood someone he never expected to see again: a shadow clone of Jack Atlas, created by the dark signer's influence.

"I change to Attack Position," Yusei declared. "Now, I activate the second effect of Synchro Backtrack —if the target has 0 ATK, I can special summon Stardust Dragon from my graveyard!"

"My turn," Yusei said calmly, drawing his card. He stared at it, then at the menacing monster, then back at his hand. He wasn't trapped. He was being tested.

"I summon (0 ATK / 0 DEF) in defense mode!"

As the white dragon dived, Yusei shouted, "I activate effect! By tributing it, I negate your monster's effect, destroying it!" The Cardian was incinerated, leaving the clone defenseless.