Arrancar Encyclopedia

The, sometimes called the Arrancar Research Time, is an omake section at the end of some of the episodes.

Overview
It provides extra information about the Arrancar and things relating to them, such as Resurrección, Hueco Mundo, Sonído, Menos Grande population, and other things related to them. The Arrancar Encyclopedia is hosted by Gin Ichimaru, although here are occasionally guest hosts such as Ichigo Kurosaki, Dondochakka Birstanne and Kaname Tōsen.

The show typically begins with Gin revealing the segment's topic. He then proceeds to go into detail with that subject, but is usually interrupted by another character, after which they or he make a joke, bringing the episode to an end. The show has had many guests, with at least one for every episode. The following have appeared on "Arrancar Encyclopedia."

Episodes
The Arrancar Encyclopedia appears after the following episodes (guest characters in parenthesis):
 * Episode 125: Introduction to Arrancar (Sōsuke Aizen).
 * Episode 127: Techniques the Arrancar use (Yammy Llargo).
 * Episode 128: When Arrancar release their Zanpakutō (Grimmjow Jaegerjaquez).
 * Episode 130: Arrancar's Numbers (Ulquiorra Cifer).
 * Episode 139: Replacing Espada (Luppi Antenor).
 * Episode 140: Hōgyoku (Kaname Tōsen, Wonderweiss Margela).
 * Episode 145: Hueco Mundo (Sōsuke Aizen and Kaname Tōsen).
 * Episode 146: Arrancar Class System (Nelliel Tu Odelschwanck in child form).
 * Episode 148: Menos Forest (Pesche Guatiche).
 * Episode 150: Dondochakka Birstanne explains his body.
 * Episode 151: Privaron Espada (Dordoni Alessandro Del Socaccio).
 * Episode 155: Animals of Hueco Mundo (Bawabawa).
 * Episode 156: Aaroniero Arruruerie.
 * Episode 157: Sword Releases (Resurrección) (Cirucci Sanderwicci).
 * Episode 159: Sonido (Gantenbainne Mosqueda).
 * Episode 168: Hollowfication (Ichigo Kurosaki).
 * Episode 174: Fracción (Szayel Aporro Granz).
 * Episode 175: Las Noches (Szayel Aporro Granz).
 * Episode 176: Yasutora Sado's Hollow-based powers (cameo by Pesche, Dondochakka).
 * Episode 185: Blue sky in Las Noches (Sōsuke Aizen,Kaname Tōsen, Wonderweiss Margela).
 * Episode 193: Szayel Aporro Granz's Zanpakutō - Fornicarás.
 * Episode 195: Nelliel Tu Odelschwanck's adult form (Nelliel in child form is the guest).
 * Episode 196: Zommari Rureaux's Sonido (Zommari and Byakuya Kuchiki guest).
 * Episode 202: Nnoitra Gilga.
 * Episode 213: Garganta (Mayuri Kurotsuchi).
 * Episode 214: Pesche and Dondochakka's True Power: Ultima and items in Dondochakka stomach.
 * Episode 220: Baraggan's Fracción (Ggio Vega and Nirgge Parduoc).
 * Episode 231: Resurreccións - Mamut, Tigre Estoque, Cierva, Leona and Anaconda
 * Episode 232: Ichigo Kurosaki tries to run the segment interviewing Starrk, Baraggan, and Harribel
 * Episode 253: Tōsen as the Gillian zoo keeper.
 * Episode 256: Ulquiorra neglects to inform Gin that their appearance has been postponed.
 * Episode 264: Gin shows what the Espada have been doing during their break.
 * Episode 267: Sword Releases (Resurrección) (Rudbornn Chelute).
 * Episode 268: Sword Releases (Resurrección) (Loly Aivirrne).
 * Episode 270: Sword Releases (Resurrección) (Ulquiorra Cifer).
 * Episode 271: Ulquiorra's Cero Oscuras.
 * Episode 274: Sword Releases (Resurrección) (Tier Harribel).
 * Episode 290: Sword Releases (Resurrección) (Kaname Tōsen).
 * Episode 297: Sword Releases (Bankai) (Gin Ichimaru).
 * Episode 307: Gin announces the closing of the segment.