Vyse was considered the original Fodder line in 2003
Fodder is any character, game, or series who would be unable to earn more than 20% of the vote against Base Link, aka finishes under 20% on the X-stats for that season. Hence the fodder line is generally considered to be an X-stat value of 20%.
Some examples of fodder include Sarah Kerrigan (14.95%), Mother Brain (16.25%), Fallout 2 (13.90%), and the Harvest Moon series (13.89%). Someone like Viewtiful Joe is not technically fodder, however, as he finished with a 21.05% value on Base Link.
Those above the fodder line but below the Noble Nine are generally considered some kind of mid-carder (high, middle, or low) - capable of winning a match, but probably only if their opponent is a low-midcarder or fodder.
Previous Fodder Lines[]
After Vyse finished at 19.05% in 2003 and then managed a nearly identical 19.21% value in 2004, the Vyse Fodder Line (or VFL) was established, saying that anyone who finished ahead of him in the standings would not be considered fodder. However, this idea had to be thrown out after Tifa crushed Vyse with 78% of the vote in the 2005 Contest; despite Tifa going on to do well against Sonic, Vyse landed at only 14.73% that year, far too low to be of any use as a fodder line. These days Isaac is most frequently cited as the standard fodder line character.