Allen Greyson is a major character in Simien 10: Blood Monkey.
Allen is an late-twenties fit Caucasian man, with black hair, green eyes, and a clean shaven appearance. He wears his Hexatrix on his left arm.
Allen is a determined and serious cop. As an officer with over 10 years in Bellwood/Undertown, Allen is knowledgeable and experienced in dealing with the various aliens coming in both cities. He seems to know most prominent alien species in Undertown.
Allen was born to a police officer father, and raised in Bellwood during most of the Ben 10 crisises.
During his high school years, Allen's father accidentally equipped a second-hand Hexatrix, mutating him into a Pyronite.
Allen followed his fathers footsteps and began working as a police officer in Bellwood, officing over the twin cities of Bellwood and Undertown and its bizarre alien cases.
At some point during his duty, Allen was lucky enough to find a Hexatrix. Approved by his police department, Allen got to keep his Hexatrix, but was limited to their choice of aliens and their limitations.
Allen is joined by a new partner in the beginning of All Falls Down, Alicia Krakowski, an officer from New York. The two work on the Zynon Mansion raid case, and later on interrogate Vender and discover of Zyrokks' return to Undertown.
- In Simien 10, Allen was named Allen Geryonson, and was a 12 year old kid who's mixed up parent DNA allowed him to shift between Pyronite, Tetramand, Petrosapien and Kinneceleran at will. This was adapted into Simien 10: Polyverse as an Osmosian hybrid in the episode The Hybrid, and finally adapted into Blood Monkey's plot using the Hexatrixes.
- Allen's previous last name, Geryonson, was a reference to the Geryon, a mythological Greek monster who was said to have one body and three faces, similar to his original ability to change between alien forms.
|Simien 10: Blood Monkey|
|Simien - Zynon - Allen - Vorkus - Ic - Omnimorph - Permbyt|
|Zyrokks - Set - Anuke - The Pyro-Knight - Spherodroids - Geodroids - Omnidroids|
|Phobius - Vrees - Sukrov - Morphius - Aglaope - King Xiv - Len Yuefo - Zilemm - Tetradeltas - Microtech - Mechachlorox - Exypnorok - Kinetisphere - Elektrakan - Aquelectran - The Sphinx - Easter Island Statues - Neimis - Nonyz - Ci - Nella - Phrominmo - Tybmrep - Vender - Urvakan - Demantur - Omnion - Ilithios - Scelerat - Exabyte - Viruses - The Time Lord|
|Aimant - Kronis - Incanton - B'hed - Ovillon - Cervelle - Helados - Vark - Skkoryz - Tes - Ekuna - Thgink-Oryp - Atmos|
|Acidrain - Forestfire - Magnetosphere - Brainfreeze - Bonecrusher - Megabite - Absorbat - Dragonfly - H2GO - Soundwave - Drillbit - Dark Hole - Whirlwind - Spikeback - Tongue Twister - Arachnophobia - Weatherize - Eruption - Flashback - Crushtacean|
|Irony - NML - Klepto - Chainsaw - Gas Planet - Atomix|
|Blackout - Greasemonkey - Brakedown - Yinyang|
|Noitpure - Ezeerfniarb - Eriftserof - Etibagem - OG2H - Naecatshurc - Niardica - Tuokcalb|
|Meltdown - Thunderstorm - Gigabite - Gasketball - Psychlone|
|Simien 10: Space Race New Aliens|
|Toxic - Physix - Scarecrow - Tentacle arms - Lightyear - Electronewt - Clockwise - Sandstone - NM8R - Elementor - Psychoplant|