Another playset, this time the infamous 'waterfall' that played such a big part in both the cartoon scenery and in the My Little Pony comic stories :) There are two waterfalls in  existance...and since there are two waterfall ponies it would be logical to assume that one goes to each. However, Hasbro were never quite that simplistic...
The two types of waterfall are as follows. Firstly, the American (and it seems Dutch) issue, featuring Sprinkles *only*. This waterfall came with a WHITE base, as if to represent clouds and was never sold with any pony other than Sprinkles.
The second type of waterfall came with a GREEN base, as if to represent grass. This issue belongs to the UK and was sold FIRST with Sprinkles and then reissued with Cascade. The accessories are the same on every issue, including Duck Soup the duck, and only the colour of the base distinguishes one from the other.
I have not seen a box with Cascade pictured - naturally most kids bought the waterfall when it first came out with Sprinkles and so less bought the reissue. Equally it was never a sturdy playset and more often than not broke, probably leading to many being thrown away. Cascade is also never mentioned in the comics, only in the fact file. I have been told that Cascade DID appear on her box - so I'm on the lookout for one to verify this positively once and for all :)
  In fact, if it were not for two important bits of evidence, Cascade and the Waterfall might never have been matched up together. First is an entry in Hasbro's own list marked 'My Little Pony Waterfall with Cascade Pony'. The second is the insert which clearly illustrates Cascade with the playset. Even though Cascade was issued the year after Sprinkles, I thought it wisest to keep them together :) Many thanks to Garej for the use of the Argos catalogue photograph of Cascade and Waterfall (right)!
Recently I discovered that Cascade does make a single My Little Pony story appearance - she is in the very first My Little Pony annual! :D