Its played in elemental decks alongside the incarnations like Solitude and Fury
Like the other Merlin shapeshifting forms among Rise of the Floodborns amethyst cards, Merlin, Goat gives you something both as it enters play and leaves play
That means you will always have to make sure you have at least three attacks before you can defeat him, unless you leave him at zero life for the turn
With Mishras Bauble in the format, Delirium is easy to achieve, so I see the card continuing to over perform
It's one of those 'selfish' minions Black often gets, and the flavour does work for a 'foul' familiar -- instead of being undyingly loyal to its summoner, it just stops short at being willing to take a hit for its master
The text is Deal 1 damage to chosen character