What is the name of the green dude in sonic?

Answer 1

There are several. Manic the Hedghog was the laid-back skater/surfer boy brother from the TV series "Sonic Underground". Scourge the Hedgehog is the "anti-Sonic" version from Moebius in the Archie comic series "Sonic the Hedgehog"; a womanising, rude, crude, evil hedghog with the same abilities and powers as Sonic. Ashura the hedgehog is a fan name given to a glitched green and black coloring of Sonic from a glitch in Sonic the Hedgehog 2. Due to being a palette glitch, has no backstory and no given personality whatsoever, this leaves it wide open for fanfiction writers to form his personality and his backstory.

Unless you're not talking about a hedgehog at all. Then...

Vector the Crocodile is most popularly known as the team leader and the Power form of Team Chaotix in Sonic Heroes. His first actual apperance was in Knuckles' Chaotix. He was also in a stage in Shadow the Hedgehog, and appears in Archie Comic "Sonic the Hedgehog", usually in storylines involving Knuckles and the Chaotix. Vector is the head honcho of the Chaotix Detective Agency, and will take almost any job so long as the pay is right. He has a rough demeanor, and at times he is even downright rude, but deep down he's actually quite a kind soul, and has been known to occasionally do cases for free (such as finding children's lost toys).

Jet the Hawk is the leader of the Babylon Rouges, in Sonic Riders. He is Sonic's rival in the game.

Bean the Dynamite is a green duck in Sonic Fighters AKA Sonic Championship and in the Archie Comic series. He enjoys throwing bombs at people, but is known to not be very bright, often distracted by "shinies", or shiny objects.

There are alot of other "green dudes" in the Sonic series, but if this doesn't answer your question, try searching it or being more specific, please. Hope this helped.