While playing FU the player will witness an expanded universe compared to vanilla, new stars, planets, biomes and much more in the way of weapons, armor and quests. The player may also witness a variety of new status effects. In FU the player can now play as one of ten new races alongside the now accessible non-playable vanilla races.
Players also lose their ambient glow, causing other forms of light to be necessary for exploring dark areas.
Frackin' Races is a separate modification that adds additional traits and abilities to the base races, FU races and even a selection of other third-party races, adding depth and consequences to one's choice in race.
A list of racial traits and supported custom races is available at http://sayterdarkwynd.github.io/races3.html