|This article is about a/an episode in Juken Sentai Gekiranger.|
Sixteenth Lesson - Jiri-Jiri! Confrontation Beast Hall, Extra-curricular Class (修行その16 ジリジリ！臨獣殿、課外授業 Shugyō Sono Jūroku: Jiri-Jiri! Rinjūden, Kagai Jugyō) is the sixteenth episode of Juken Sentai Gekiranger. It focuses on Rageku's training of the RinJyuKen warriors and further reveals the background of the rebellion that split the Juken schools in the past.
Rinjuken Master Rageku uses Rio to force Mele into a showdown with a powerful opponent in order to awaken their true potential.
The revived Rageku arrives at the Rin Jū Hall to meet Rio. However, much to Kata's distaste, Rageku favors Mere more than Rio. When Mere refuses to prove herself by fighting Rio, Rageku poisons Rio as her way to start Rio on the path of suffering and to start Mere's training with a foe of her choosing. Rageku then attacks the city and easily defeats Geki Tohja, with Xia Fu's appearance leading to a revelation on the origins of the Seven Kensei and the Three Kenma as the first Jūken Masters, until they assumed their current forms and founded the two opposing schools before the Geki -Rin Rebellion that led to the Demons' defeat. Rageku then forces Mere to fight Xia Fu, immobilizing the Gekirangers to ensure no interference. In order to win, Mere uses Infinite Waves on herself to fight at full strength despite her own internal pain. Rio watches while the poison courses through him, until he overpowers Rageku's Ringi and save Mere from sacrificing herself to kill Xia Fu. After a brief fight, Rio defeats Rageku, though she reveals that she was only testing him for his jealousy of Mere being able to overwhelm Xia Fu. Rageku then took Rio and Mere as her disciples while as the Gekirangers start training harder.
- Jan Kandou (漢堂 ジャン Kandō Jan): Hiroki Suzuki (鈴木 裕樹 Suzuki Hiroki)
- Ran Uzaki (宇崎 ラン Uzaki Ran): Mina Fukui (福井 未菜 Fukui Mina)
- Retsu Fukami (深見 レツ Fukami Retsu): Manpei Takagi (高木 万平 Takagi Manpei)
- Master Sha-Fu (マスター・シャーフー Masutā Shā Fū, Voice): Ichirō Nagai (永井 一郎 Nagai Ichirō)
- Miki Masaki (真咲 美希 Masaki Miki): Kazue Itoh (伊藤 かずえ Itō Kazue)
- Rio (理央 Rio): Hirofumi Araki (荒木 宏文 Araki Hirofumi)
- Mele (メレ Mere): Yuka Hirata (平田 裕香 Hirata Yuka)
- Sky Fist Demon Kata (空の拳魔カタ Sora no Kenma Kata, Voice): Rokurō Naya (納谷 六朗 Naya Rokurō)
- Sea Fist Demon Rageku (海の拳魔ラゲク Umi no Kenma Rageku, Voice): Naoko Kouda (幸田 直子 Kōda Naoko)
- As part of Super Hero Time, this episode aired alongside Kamen Rider Den-O episode 19, That Man, Zero's Start
- Viewership: 6.3%
- Pre-Credits: Seven Sage Masters of Geki Juken
- This is the second time that Rio defeated a Kenma's Ringi;The first time was during Lesson 12,when he defeated Kata's Darkness Cannon
- This episode reveals the initial human forms of all the former Sages who took part in the Beast Rebellion, including five who haven't appeared yet.
Juken Sentai Gekiranger Volume 4 features episodes 13-16: Lesson 13: Shin-Shin! The Spirit's Dance, Lesson 14: Netsu-Netsu! Forget Your Techniques, Lesson 15: Howa-Howa! Mama Work, and Lesson 16: Jiri-Jiri! Confrontation Beast Hall, Extra-curricular Class. 
- Pushed to the Edge - Power Rangers counterpart in Gekiranger. See comparison page. (Megazord fight footage & story)