Over time, a number of backgrounders have risen to the rank of character. That is, they have at the least obtained a name, though some have even grown to receive a doll and profile.
Keep in mind that in order to fit the definition of backgrounder-to-character, the character has to have had a period of certain lack of identity. Manny Taur and Invisi Billy may have featured in the background of several webisodes before they got involved with the storyline, but they received names before those webisodes aired through other channels. Equally, the gingerbread boy may not have a name revealed yet, but he has an origin story and voice, suggesting he is meant as a character too.
Archer debuted in "Fear Pressure" and went on to appear rarely and irregularly throughout Volume 2. His Volume 3 appearances are even more limited, but he was formally introduced by the end of Volume 3.
Herbert East is presumably a troll or goblin, and one of the handful of Volume 1 backgrounders that made only one appearance in Volume 1, in "Mad Science Fair", though was brought back for inclusion in the CGI TV specials. His usual fate is to be grabbed by a tentacle and pulled into a locker or other crevice.
Iris Clops debuted in "Talon Show" and received a name one and a half year later in the Gory Gazette. Even later, she received a doll and was lifted to full character status. From her time as backgrounder, there exist two alike models of Iris that are not her, the first being a one-time re-use of her model as fearleader of another school in "Monster Mashionals Part 1". The second is a variation of her that is purple with an orange dress - this variation remains a backgrounder.
Purple Iris appears in "Miss Infearmation", "Fright On!" and "Super Fan".
Quill Talyntino debuted in "Falling Spirits" and received a name more than three years later through the second doll election. She is a cartoon-only character that is only featured in 2D, but even though she lost she will likely get a doll eventually.
Scarah Screams debuted in "Jaundice Brothers" and received a name a year later during a competition at San Diego Comic-Con International, which she won. She was made into a doll as the exclusive of next year's SDCCI. Fictionally, she's both featured in 2D and 3D. There exist two alike models of Scarah that are not her, the first being a one-time re-use of her model as fearleader of another school in "Monster Mashionals Part 1". The second is a variation of her that is brown of skin - this variation remains a backgrounder.