Vengeance Quest

Vengeance Quest is a popular Goodfic in the Redwall fandom, written by Snowspine (a.k.a. Sounasha or makhsihed). It details the adventures of the squirrel heroine Riala Goldentail. The story is an example of how an author can improve over time; Riala started out as a decidedly Sueish RPG character, and was slowly developed into a well-rounded and interesting character.

It can be found here; it should be noted that the story is rated R for scenes of violence, non-graphic sex, and some all-round disturbing content.

This fic is the origin of Agents Stormsong and Skyfire. The fic's entire cast is comprised of original characters, none of them Sues (though a parody of famous Canon Stu Drizzt Do'Urden appears). However, canon locations such as Redwall Abbey, Salamandastron, and Castle Floret appear, and are very important to the plot (the latter is the site of the final battle).

Summary
Chapter 1: Riala Goldentail is the main character. Her father, Rilar Battlecry, has sworn to slay the infamous wolverine Nightdeath Longclaws, leader of the Nighthunt horde,in revenge for the death of his wife. Longclaws eventually finds him and challenges him to a duel, but gives his archers a prearranged signal to open fire as soon as Rilar gains the upper hand; Riala herself barely escapes being shot. Riala swears vengeance on Longclaws in turn, and goes wandering. (note: Due to an error, the page for chapter one actually contains the first four chapters.)

Chapter 2: Four seasons pass as Riala stalks the Nighthunt, making a name for herself by helping goodbeasts and fighting vermin whenever she comes across them. During her travels, she comes across a pair of weasel slavers taking a mole family prisoner, and the sounds of the moles (particularly the dibbuns) being whipped sends her into a rage; Riala quickly dispatches the first slaver by slashing his throat, and is about to kill the second when she is stopped by Soilfree. Eventually, Riala spares him, chaining him up; after a conversation with the mole family, in which she explains why she is seeking revenge, she takes the second slaver outside and interrogates him, trying to learn where the rest of his band is.