Storm Release Secret Technique: Demon Dragon Storm

Hiruko uses the Storm Release Kekkei Genkai he acquired through his Chimera Technique to produce a massive thunder cloud that can infinitely absorb chakra to grow. He can apparently channel this absorbed energy into the earth, possibly leading to a bigger technique.

Trivia

 * After Hiruko uses this technique, and the focus changes back to him from Shikamaru, his last seal changes from Tiger to a special seal. When he reactivates the technique to absorb Naruto's Great Ball Rasengan, he uses the Horse seal instead.