Best Arc or Route or Season

A topic series started by musumane, but later continued by superangelo128.

Apparently the original intent was to do shounen series but superangelo128 expanded it to visual novel routes, visual novel arcs, random other anime/manga arcs, and anime seasons.

Long-running Shounen Series
Fairy Tail: Fighting Festival, Runner up: Tenrou Island Naruto Pre- Timeskip: Chuunin Exams, Runner Up: Land of Waves One Piece: Water 7/Enies Lobby, Runner Up: Alabasta Dragon Ball Z: Cell Saga, Runner Up: Frieza Saga Bleach: Soul Society, Runner Up: Vandenrich/1000-Year War Negima: Magic World, Runner Up: School Festival Claymore Pre-Time Skip: Battle of the North, Runner Up: Teresa of the Faint Smile Rave Master/Groove Adventure Rave: King/Tower of Din, Runner-Up: Mermaid Dragon Ball: Piccolo Daimou/King Piccolo, Runner-Up: Red Ribbon Army Rurouni Kenshin: Kyoto arc, Runner-Up: Trust and Betrayal/Tsuiokuhen Jojo's Bizarre Adventure: Part 2 Battle Tendency, Runner-Up: Part 4 Diamond is Unbreakable Naruto Post-Time Skip: Invasion of Pain, Runner-Up: Hidan and Kakuzu Hunter x Hunter: Chimera Ant, Runner-Up: Yorknew City Yu Yu Hakusho: Dark Tournament, Runner-Up: Chapter Black

Other Series
Humanity Has Declined: The Fairys Survival Skills, Runner Up: The Fairies Time Management Digimon Adventure/Season 1: Myotismon Saga, Runner Up: Dark Masters Saga Amagami SS: Ai Nanasaki arc, Runner Up: Haruka Morishima arc Kanon 2006: Makoto Sawatari arc, Runner Up: Mai Kawasumi arc Yu-Gi-Oh Duel Monsters: Battle City, Runner Up: Waking the Dragons/Orichalcos Toriko: Century Soup, Runner Up: Mellow Cola/Cooking Festival Tengen Toppa Gurren Lagann: Lagann-hen, Runner-Up: Post-Time Skip in original series Digimon Adventure 02/Season 2: Digimon Emperor/Kaiser, Runner-Up: Destiny Stones The World God Only Knows (what anime's covered): Shiori Shiomiya arc, Runner-Up: Tenri Ayukawa arc Mirai Nikki: 11th/Akise Aru arc, Runner-Up: Yuno arc Sailor Moon: Death Busters arc, Runner-Up: Dark Kingdom arc Yu-Gi-Oh GX: Darkness arc, Runner-Up: Dimension World arc Black Lagoon: Hansel and Gretel, Runner-Up: Japan To Aru Majutsu no Index: Sisters, Runner-Up: Academy City Invasion Haruhi Suzumiya (anime only no side stories): Disappearance, Runner-Up: Endless Eight -monogatari series: Tsubasa Cat, Runner-Up: Nekomonogatari Black/Kuro Busou Renkin: Papillion arc, Runner-Up: L.X.E and Kazuki Re-Extermination TIED Code Geass: Ragnarok/Emperor Lelouch, Runner-Up: Euphinator World God Only Knows (manga-only pre-godesses): Body Switch/Yui Goldo, Runner-Up: Ramen Girl/Sumire Uemoto Futari wa Precure: Movie 2/Ice Twins, Runner-Up: Stuff before Porun appears Kara no Kyoukai: 5: Mujun Rasen/Paradox Spiral, Runner-Up: 3: Tsuukaku Zanryuu/Remaining Sense of Pain Pretty Cure Splash Star: TIE between Kintoleski and Akudaikan Pokemon anime: Diamond&Pearl/Sinnoh, Runner-Up: Season 1/Kanto Yu-Gi-Oh 5Ds: Dark Signers, Runner-Up: TIE between Fortune Cup and WRGP Kaiji: E-card, Runner-Up: Bog Heartcatch Precure: Dune arc, Runner-Up: Blossom/Marine and Sunshine TIED World God Only Knows Awakening the Goddesses: Mercury, Runner-Up: Mars Evangelion: End of Evangelion, Runner-Up: Episodes 8-18

Best Seasons
Sayonara Zetsubou Sensei: Season 1, Runner-Up: Zan Hidamari Sketch: x Hoshimittsu, Runner-Up: x 365 Slayers: NEXT, Runner-Up: Season 1 Major: Season 1, Runner-Up: Season 5 Maria-sama ga Miteru: Season 1, Runner-Up: Season 2/Haru and 3rd TIED

Visual Novels
Higurashi no Naku Koro ni: Episode 6: Tsumihoroboshi/Atonement, Runner Up: Episode 5: Meakashi/Eye Opening Muv-Luv Extra: Marimo route, Runner Up: Sumika route Katawa Shoujo: Rin route, Runner Up: Hanako route Ever17: Coco route, Runner-Up: Tsugumi route Tsukihime: Kohaku route, Runner-Up: Hisui route Clannad: After Story, Runner-Up: Tomoyo OVA/route Sharin no Kuni: Chapter 5, Runner-Up: Houzuki Fandisc chapter Umineko no Naku Koro ni: Episode 3: Banquet, Runner-Up: Episode 4: Alliance G-senjou no Maou: Chapter 5/Haru, Runner-Up: Chapter 4 excluding Mizuha ef: RenjixChihiro, Runner-Up: YuuxYuuko Little Busters VN: Refrain, Runner-Up: Haruka route Muv-Luv Alternative: PTSD arc, Runner-Up: Original Hive arc Cross+Channel: Miki route, Runner-Up: Week 6 Hoshizora no Memoria: ***/??? Route, Runner-Up: Komomo route Sengoku Rance: True History route, Runner-Up: Kenshin route Crescendo: Ayame route, Runner-Up: Miyu and Yuka route TIED Deus Machina Demonbane: Al Azif route, Runner-Up: Ruri Hadou route Saya no Uta: Ending C, Runner-Up: Ending B Symphonic Rain: Al Fine, Runner-Up: Phorni route Rewrite: Moon, Runner-Up: Akane route Yume Miru Kusuri: Aeka route, Runner-Up: Mizuki Route Fate/Stay Night: Unlimited Blade Works, Runner-Up: Heaven's Feel