Prototype giants: Star Catcher, Star Swirl, Butterscotch (the Butterscotch went up on ebay many years ago and ended up in a giant plush collector’s hands
the other two were only seen in photographs on the manufacturer’s website before the actual line went into production)
Prototype half-size “sample” giants: Rainbow Dash and Sweetberry confirmed/sold to collectors, when asked a representative mentioned there were five sample characters made
Australian colouring competition prizes: Kimono (I believe two exist)
US Pony Points mail order: Frilly Frocks (they initially produced only 10 numbered editions of her believing nobody would get enough points
when they received way more entries the MO was closed and only enough produced to meet the standing orders, I believe numbers like 100-200 of her have been thrown around)