Siege Rhino (2014), Dragonlord Ojutai (2015), and Thalia, Heretic Cathar (2016)
Kataki, War's Wage Affinity flat out loses to this if it's timely enough and doesn't have the Galvanic Blast, and can still struggle even if the timing is suboptimal
Other than that, it doesnt have a whole lot going for it anymore, and you can easily replicate the experience with a much cleaner looking site
Copying a creature and giving it a combat research type effect is really nice
Combos like Diablo - Devoted Herald in Emerald/Steel discard make Beyond The Horizon extremely powerful
Bear in mind as well that if your opponent doesnt find a way to deal with Jafar on their turn, which is definitely a risk with their hand of seven new cards, then you can just sing A Whole New World again if you drew it from the last one