Ben firsts transforms into Spidermonkey when he has to fight off his Anodite grandmother in the episode "What Are Little Girls Made Of?".
Spidermonkey is an alien with 4 arms and 2 legs, a feature Spidermonkey has in common with Fourarms. Spidermonkey can spin webs from his tail, has supernatural adhesive skills, and has superhuman agility.
Spidermonkey is one of the aliens to be the weakest, he dosnt have much strengh and can get tangled by his own web.
Spidermonkey is an Arachnichimp from the planet Aranhaschimmia. The name "Arachnichimp" is derived from arachnid, the name of a group of animals including spiders, scorpions, and ticks, among others, and chimpanzee, a type of ape. Oddly, Spidermonkey has a tail, a feature chimps (and indeed, the hominids as a whole,) do not posses.
He is based on four arms (apart from the super strengh) and wildmutt also a hairy alien