"Polymerization!" Leo shouted with his usual gusto. "I fuse Elemental HERO Clayman and Elemental HERO Sparkman! To secure my victory, I'm bringing out a new champion! Rise, Elemental HERO Grandmerge (0/0)!"
"What do you plan to do with a monster that has zero Attack points?" Alex shouted from across the field. "Take this seriously, Leo!"
"Grandmerge's Attack becomes the combined original Levels of its materials times 300!" Leo explained proudly. (Grandmerge: 0 → 2400 ATK).
"That's still not enough to take down my XYZ-Dragon Cannon (2800/2600)!"
"I'm not done yet!" Leo smirked. "I activate the Field Spell Skyscraper! When an 'Elemental HERO' attacks a monster with higher ATK, it gains a 1000-point boost during damage calculation! Go, Grandmerge! Skyscraper Strike!" (Grandmerge: 2400 → 3400 ATK).
The fusion monster shattered the mechanical dragon. (Alex's LP: 2000 → 1400).
"Now, Grandmerge's second effect! When it destroys an opponent's monster by battle, I can Tribute it to Special Summon any 'Elemental HERO' Fusion Monster from my Extra Deck, ignoring its Summoning conditions! Come forth, Elemental HERO Flame Wingman (2100/1600)! Now, Wingman, direct attack! Burn!"
Alex flinched at that word. A sharp sense of déjà vu washed over him, nearly making him forget he was in a duel. At the last second, he snapped back to reality.
"Counter Gate!" Alex yelled. "When you declare a direct attack, I can negate it and draw one card! If it's a monster, I can Normal Summon it immediately!" Alex drew, but it wasn't a monster he could use. However, Flame Wingman's attack was halted.
"Oh, come on!" Leo groaned. "I was so sure I had it this time! I end my turn."
Alex was lost in thought. 'Burn?' Where have I heard that tone before? No, focus... I'm in the middle of a duel.
"My move! Draw! I activate Monster Reborn! Return to the field, XYZ-Dragon Cannon! Now, I discard one card to activate its effect: destroy Flame Wingman!"
"Aw, man! Not again!" Leo lamented.
"Now, direct attack! Go, Dragon Cannon!" (Leo's LP: 1000 → 0).
As the holograms flickered out, Leo stood up and laughed, brushing off the dust. "Maybe next time! I just need to prep a bit more. What do you say, Alex? Hungry?"
Alex started, pulled abruptly from his musings. "Uh—no, I can't. I just remembered I have something... really important to do. See you later!"
"Alright!" Leo called out cheerfully, watching his friend sprint away.
Alex ran through the Academy halls, heading straight for the infirmary. A single thought echoed in his mind: It can't be. It's impossible. He burst into the room where Luna was sitting up in bed, meticulously re-evaluating her deck.
"Luna! We have a problem. I think I know who HellKing is."
"What?" Luna nearly dropped her cards in shock. "How could you possibly know?"
"Think back. What did he shout when he attacked you with Red Dragon Archfiend?"
"He said something like, 'Burn in the flames of hell.' Why?"
"Leo says something almost identical when he attacks with Flame Wingman," Alex explained, his voice low. "He just says 'Burn,' but the intensity... it's the same."
Luna looked at him skeptically. "Are you suggesting Leo is HellKing? That's impossible. Leo can barely win a lunchtime duel."
"I don't know for sure, but we have to defeat HellKing to find the truth. And I need your help to do it."
"Why me?"
"Because you're the 'First-Year Queen.' You're the strongest duelist I know. And besides... if HellKing really is Leo, your deck is the only one meant to stop him."
"How? I already lost once."
"Because your deck was incomplete," Alex said, echoing the words they had heard before. "Leo made me realize it when he told the story of Zera. He told the tale of a warrior who ascended to fight alongside the heavens. But every heaven needs a ruler. A leader. Someone who wasn't in your deck... until now."
Alex reached into his pocket and pulled out a single card. When Luna saw it, she practically leaped out of bed and snatched it.
"Well then," Luna said, a fierce light returning to her eyes. "What are we waiting for? Let's unmask this 'King'."