Yu - Gi - Oh ! GX - Episode 172 " Duel Academia in Peril ! The Crystal Beasts Block the Way " , known as " Duel Academia in Peril ! The Gem Beasts Block the Way " in the Japanese version , is the one hundred and seventy - second episode of the " Yu - Gi - Oh ! GX " anime . It first aired in Japan on January 30 , 2008 . Summary . As the KaibaCorp building in Domino City explodes around him , Jaden searches for a way out . He escapes in a , but the rope snaps , though he manages to jump to a second gondola - whose rope also snaps . Jaden Summons " Elemental Hero Neos " using Yubel ' s powers to manifest the spirit physically . Neos saves him , and Jaden makes it back to the motorcycle that Sartorius has used , and takes it , heading for the docks to find a way back to Duel Academy . Back on the island , Trueman has taken the form of Daigo Sorano , and challenges many Duelist s using his numerous clones . All accept , as they are having problems finding opponents for the Graduation Duel , due to the disappearance of those that Trueman has already defeated . Hassleberry is still searching for Sorano in the forest , and one of the Trueman - Sorano clones appears to challenge him as well . He suggests that Hassleberry stop hanging around with Jaden , and states that in doing so , he looks down on younger students . Hassleberry replies that that ' s absurd - Sorano was the first friend that the made at Duel Academy , even though Sorano was in Obelisk Blue and Hassleberry in Ra Yellow . Trueman attempts to exploit the darkness in Hassleberry ' s heart , but is unable to , and he comments he didn ' t expect there to be anyone able to resist him besides Jaden . Realizing that Sorano is really Trueman , Hassleberry accepts his challenge , and both activate their Duel Disk s . Back in Domino , Jaden seems to be fatigued , and nearly drives Sartorius ' motorcycle into the ocean , but he jumps off in time . Jaden meets who appears to be another clone of Trueman , but this one acts differently , even expressing concern for Jaden ' s current condition . Convinced that it ' s Trueman , Jaden begins a Duel with him . Trueman Summons multiple Crystal Beast s and Jaden realizes that he must have already defeated Jesse . Trueman responds that he will attack to wake Jaden up . During Jaden ' s second turn , Trueman activates " Mine Blast " which sends his final three Crystal Beasts to the Graveyard , and the activates " Rainbow Gravity " to Special Summon " Rainbow Dragon " . When he attacks with it , " Polymerization " flies out of Jaden ' s Graveyard , and a dark aura disperses from it . Suddenly , Jaden can see clearly - he ' s not Dueling Trueman , he ' s Dueling Jesse . Having gotten Jaden ' s senses back to him , the Duel ends . Jaden determines that his " Polymerization " card was infected by the darkness in " Arcana Force 0 - The Fool " . Crystal Beast Sapphire Pegasus appears , and tells Jaden and Jesse that both of them overcame the darkness in their own hearts - and together , they should be able to stop Nightshroud . At Duel Academy , the Duel between Trueman and Hassleberry is underway , and Hassleberry has been reduced to less than half of his Life Points by " Horus the Black Flame Dragon LV8 " . Hassleberry Summons " Hyper Hammerhead " and attacks " Horus " , reducing his own Life Points to 200 . However , the effect of " Hyper Hammerhead " returns " Horus " to Trueman ' s hand , and thus Hassleberry can play Spell Card s again . Using " Spacetime Transcendence " , Hassleberry removes Dinosaur - Type monsters in the Graveyard from play and Summons " Tyranno Infinity " , whose attack points increase for each Dinosaur removed . Since he can ' t attack this turn , as his Battle Phase has already ended , Hassleberry plays " Dino Blast " , dealing Trueman 1200 damage . Trueman again determines that there is no darkness in Hassleberry ' s heart for him to exploit - so he ' ll just have to create some . Trueman creates a vision in Hassleberry ' s head , and takes him back to his " past life " as a . However , as such , he is a carnivore - and thus feeds on other dinosaurs , which is something that Hassleberry had never given much thought . Trueman then suggests that the dinosaur bone implanted in Hassleberry ' s leg is the bone of a dinosaur he ate in his past life . He then causes Hassleberry to hallucinate that he ' s been attacked by the dinosaurs he supposedly consumed in his past life . He then continues the Duel , and resummons " Horus the Black Flame Dragon LV8 " and plays " Burial from a Different Dimension " to return three removed Dinosaur - Type monsters to Hassleberry ' s Graveyard , thus reducing the ATK of " Tyranno Infinity " to 1000 . He attacks , wiping out the rest of Hassleberry ' s Life Points and absorbing him into the World of Darkness . Elsewhere , Jaden and Jesse are en route back to Duel Academy in a speedboat . Featured Duels . Jaden Yuki vs . Jesse Anderson . Turn 1 : Jaden Jaden draws " Elemental Hero Burstinatrix " and subsequently Normal Summons it ( 1200 / 800 ) in Attack Position . He then Set s a card . Turn 2 : Jesse Jesse draws . He then Normal Summons " Crystal Beast Cobalt Eagle " ( 1400 / 800 ) in Attack Position . Jesse then activate s " Golden Rule " equip ping it to " Cobalt Eagle " . Upon activation , the first effect of " Golden Rule " activates , letting Jesse take " Crystal Beast Ruby Carbuncle " and " Crystal Beast Emerald Turtle " from his Deck and place them in his Spell & Trap Card Zone as Continuous Spell Card s . Jesse then activates the second effect of " Golden Rule " to Special Summon " Crystal Beast Amethyst Cat " ( 1200 / 400 ) in Attack Position . He then activates " Crystal Beacon " to Special Summon " Crystal Beast Topaz Tiger " ( 1600 / 1000 ) from his Deck in Attack Position . " Topaz Tiger " attacks " Burstinatrix " . The effect of " Topaz Tiger " activates , increasing its ATK by 400 during the Damage Step only ( " Topaz Tiger " : 1600 → 2000 / 1000 ) , but Jaden activates his face - down " Mirror Gate " to switch control of both battling monsters before damage is calculated . " Topaz Tiger " destroys " Burstinatrix " ( Jesse 4000 → 3200 ) . After the Damage Step , the effect of " Topaz Tiger " expires ( " Topaz Tiger " : 2000 → 1600 / 1000 ) . " Amethyst Cat " attacks directly via its own effect at the cost of halving the Battle Damage Jaden takes ( Jaden 4000 → 3400 ) . Jesse then activates " Rare Value " to send " Ruby Carbuncle " in his Spell & Trap Card Zone to the Graveyard and draw two cards . Since a monster placed in the Spell & Trap Card Zone via " Golden Rule " has left the field , " Golden Rule " is destroyed . Subsequently " Crystal Beast Amethyst Cat " is destroyed too due to the last effect of " Golden Rule " . Jesse activates " Crystal Spring " . Now whenever a Crystal Beast is returned to Jesse ' s Deck , he can take two Crystal Beasts from his Deck and place all three cards on of his Deck in any order . Jesse then activates the effect of " Crystal Beast Cobalt Eagle " to return " Emerald Turtle " to the top of his Deck . Jesse then activates the effect of " Crystal Spring " to place " Emerald Tortoise " , " Crystal Beast Sapphire Pegasus " and " Crystal Beast Amber Mammoth " on top of his Deck . Jesse sets two cards . On Jesse ' s End Phase , control of " Crystal Beast Topaz Tiger " returns to Jesse . Turn 3 : Jaden Jaden draws " Polymerization " and subsequently activates it to fuse " Elemental Hero Avian " with " Elemental Hero Bubbleman " and " Elemental Hero Sparkman " in order to Fusion Summon " Elemental Hero Tempest " ( 2800 / 2800 ) in Attack Position . " Tempest " attacks " Cobalt Eagle " , with Jesse activating his face - down " Mine Blast " to send the top five cards of his Deck to the Graveyard ( " Rainbow Life " , " Ancient City - Rainbow Ruins " , " Emerald Turtle " , " Amber Mammoth " and " Sapphire Pegasus " ) , but he cannot conduct his Draw Phase during his next turn . Jesse then activates his face - down " Rainbow Gravity " to Special Summon " Rainbow Dragon " ( 4000 / 0 ) from his Deck in Attack Position , as all seven Crystal Beasts are either on the field or in the Graveyard . A replay occurs , but since " Rainbow Gravity " was used to summon " Rainbow Dragon " , all of Jaden ' s Attack Position monsters must attack " Rainbow Dragon " , so " Tempest ' s " attack is redirected to " Rainbow Dragon . " " Rainbow Dragon " then destroys " Elemental Hero Tempest " ( Jaden 3400 → 2200 ) . The aftershock from the attack is so powerful , it knocks " Polymerization " out of Jaden ' s Graveyard . This action purifies " Polymerization " of the darkness infecting it , which subsequently removes the dark spell Jaden is under . After Jaden sees that he is Dueling Jesse instead of Trueman , the Duel is called off . Tyranno Hassleberry vs . Trueman . The Duel is shown from an unspecified point . Hassleberry has " Destroyersaurus " ( 1800 / 1100 ) in Attack Position and 2900 Life Points , while Trueman has " Horus the Black Flame Dragon LV8 " ( 3000 / 1800 ) in Attack Position and " Royal Decree " on his side of the field as well as 2600 Life Points . Due to the effect of " Royal Decree " , all other Trap Cards are negated . Trueman ' s turn " Horus the Black Flame Dragon LV8 " attacks and destroys " Destroyersaurus " ( Hassleberry 2900 → 1700 ) . Hassleberry ' s turn Hassleberry draws " Hyper Hammerhead " and subsequently Normal Summons it ( 1500 / 1200 ) in Attack Position . " Hyper Hammerhead " then attacks " Horus the Black Flame Dragon LV8 " . " Horus the Black Flame Dragon LV8 " then destroys " Hyper Hammerhead " ( Hassleberry 1700 → 200 ) , but this activates the latter ' s effect , returning " Horus the Black Flame Dragon LV8 " to Trueman ' s hand . Hassleberry then activate s " Spacetime Transcendence " to remove from play " Dark Driceratops " , " Gilasaurus " , " Destroyersaurus " and " Hyper Hammerhead " from his Graveyard in order to Special Summon " Tyranno Infinity " ( ? / 0 ) in Attack Position . Due to the effect of " Tyranno Infinity " , it gains 1000 ATK for each Dinosaur - type monster that is currently in Hassleberry ' s Removed from Play Zone . There are currently four ( " Tyranno Infinity " : ? → 4000 / 0 ) . Hassleberry then activates " Dino Blast " to inflict damage to Trueman equal to the Level of " Tyranno Infinity " times 300 . " Tyranno Infinity " is Level 4 ( Trueman 2600 → 1400 ) . Trueman ' s turn Trueman draws " Premature Burial " and subsequently activates it to pay 800 Life Points ( Trueman 1400 → 600 ) and Special Summon " Horus the Black Flame Dragon LV6 " ( 2300 / 1800 ) from his Graveyard in Attack Position . He then activates " Magical Stone Excavation " to discard " Level Down ! " and " Level Modulation " and add " Level Up ! " from his Graveyard to his hand . Trueman then activates " Level Up ! to send " Horus the Black Flame Dragon LV6 " to the Graveyard and Special Summon " Horus the Black Flame Dragon LV8 " from his hand ( 3000 / 1800 ) in Attack Position . He then activates " Burial from a Different Dimension " to return " Gilasaurus " , " Dark Driceratops " and " Destroyersaurus " from the Removed from Play Zone to Hassleberry ' s Graveyard ( " Tyranno Infinity " : 4000 → 1000 / 0 ) . " Horus the Black Flame Dragon LV8 " attacks and destroys " Tyranno Infinity " ( Hassleberry 200 → 0 ) . Featured cards . The following cards appeared in this episode . Cards in italics debuted here .