Simian

Simian is a character introduced in second season of Ben 10: Alien Force, an Arachnichimp from the planet Aranhaschimmia. He first appeared in Birds of a Feather. Then he returns in Simian Says.

Powers and Abilities
Like all Arachnichimps, he has enhanced agility, can stick to walls, spin webs, shoot webs from his tail and he is also very skilled in hand-to-hand combat able to defeat multiple DNAliens in rapid succession with ease.

Alien Force
Simian appeared for the first time in Birds of a Feather, where, coming on Earth, he met Ben (as Spidermonkey), Gwen and Kevin being attacked by a group of DNAliens. Mistaking Spidermonkey for a true Arachnichimp, Simian interfered in the fight and forced the DNAliens to leave, saving the group. When learning he had actually saved "Ben 10" and his team, he declined their offer to join their team to fight DNAliens, stating he couldn't. He also said that he didn't know anything about DNAliens.

Later however, Ben surprised him when he was stealing equipment from a cryogenics lab. He helped him to escape as Goop, but asked for an explanation. Simian then replied he was the Prince of Aranhaschimmia and to prove he was a valuable king, had to get and bring back to his planet a crystal from a base on Earth's moon. Feeling empathy for him, Ben decided to help him and convinced reluctant Gwen and Kevin to come too.

Arriving on the moon, the group successfully passed through the base's defenses, even being crushed before spraying the acid on the floor, but Ben started having doubts about Simian's motivations when the Arachnichimp asked him to attack Lu, the harmless guard of the base, and tried to kill him himself when Ben refused. It was eventually revealed that Simian had lied to Ben, and was actually a mercenary hired by a Highbreed to steal the crystal, which was the power source of a communication base needed by the Plumbers to protect Earth from the inevitable Highbreed invasion. He pushed Kevin aside when he made his escape.

Ben later stated that he fully doubted Simian when he mentioned the DNAlien's acid, because Simian said he had no idea who DNAliens were at the beginning of the episode.

When bringing the crystal back to his client, Simian realized too late that Ben had replaced the crystal inside the container with a DNAlien ear cleaner filled with worthless, but powerful alien acid. Thinking this was a bad joke from Simian, the Highbreed chased after Simian and seemingly stuns him with the acid. However, the Highbreed changed his mind to the Highbreed ships and lock him.

Ultimate Alien
Simian was imprisoned, but he escaped and returned in Simian Says after they encountered a problem using a Xenocyte. He then headed to his homeworld where he sold the Xenocyte to Mizaru, a crime lord. However, the Xenocyte broke loose of the container and attacked Mizaru, forcing Simian to plead for Ben's help as later the Arachnichimps were being converted into DNAliens, though they slightly look different than humans infected with Xenocytes. At first, the group was reluctant but agreed to aid him.

At the end of the episode, Simian sold a DNA ray gun he found earlier to Emperor Milleous, revealing he has returned to his criminal ways (thus proving that Kevin was right about him).

Ben 10: Alien Force

 * Birds of a Feather (first appearance)

Ben 10: Ultimate Alien

 * Simian Says (first re-appearance)

Trivia

 * Simian is the first Arachnichimp criminal/villain to appear in the series.
 * In many ways, Simian is very similar to Argit, however unlike Argit, he has been shown to be capable of being selfless and/or helping others (Argit would only help others if it helped him and/or if he could profit/benefit from it).
 * Higher primates are called Simian in biology.