So, I think that the Shipwrecker CMC that I had people help me put together last year might just work better as Pony cards rather than their own special card type that needs explaining, buuuuuuuut I think the current way I have it worded is unnecessarily clunky.
[Ability name] (Shipwreck): While this card is in your hand, you may discard this card to discard one Ship from the grid. If you use 3 Shipwrecker cards in the same turn, discard every card from the grid except the start card. This power cannot be copied.
I modeled the wording after the guide for Replace, but there's a few things I feel don't work. Firstly, is there any reason to keep the "cannot be copied" clause? I may have misunderstood how Copy works if this line is necessary, because I always thought the pony had to be on the grid for it to copy another card. Alternatively, if the copy ability is technically active while in your hand, would the Shipwreck ability be too powerful if it could be copied? (That last one might be something I should test.)
Secondly, wouldn't it be more elegant to say "Discard this card from your hand to X" without the "While this card is in your hand" clause? As long as "from your hand" is specified, that explicitly means you cannot use it from the grid, and it cuts out a lot of what seems to me unnecessary wording.
Lastly, the secondary ability of nuking the board if you play 3 of them probably needs to be slightly rephrased to refer to the Shipwreck ability rather than the Shipwrecker card names since that limits future Shipwrecker ponies to always need that title.