War of the Spark continues its march through preview season, and it feels more like a sensory assault than any set before it. There are Elderspells and 10,000 planeswalkers and giant Boar Gods and Vintage-playable legendary artifacts and Turn 3 kills and infinite combos and it's all just so much to process at once. For this reason, I can't fault anyone for overlooking what feels like another in a long line of Clone variants.
Here's the thing about that lineage of Clone variants, though: a lot of them hit in Standard.
Vesuvan Doppelganger and Clone were some of the hottest cards around when I got my introduction to Magic way back in the Stone Age. Sakashima the Impostor played an important role in Hypergenesis decks. Vesuvan Shapeshifter was an unlikely combo piece along with Brine Elemental in Time Spiral-era "Pickles" lock decks. Phantasmal Image has copied every creature from Progenitus to Champion of the Parish. And Vizier of Many Faces was just a key card in The Scarab God wars of last year's Standard format. How, then, does Spark Double compare to its predecessors?
In one very key sense, Spark Double is dramatically worse. Unlike all these examples, Spark Double can only copy a creature you control. When your battlefield has been effectively dealt with, Spark Double will always be awful. This is a huge strike against Spark Double's Constructed playability, as one of the key tenets of successful deckbuilding is a focus on flexibility and minimizing fail states. In some instances, though, the upsides of a narrow card can combine to make an option worth building around. Spark Double is doing several things we just don't expect to see in a four-mana Clone.
First and foremost, Spark Double gains the capability to copy a planeswalker. With the aforementioned 10,000 new planeswalkers ready to redefine how games of Standard are played, this is an opportune time for the upgrade. Speaking of upgrades, Spark Double provides one for whatever creature or planeswalker it's copying in the form of increased loyalty or power and toughness. Finally, Spark Double will not take on the legendary subtype of whatever it's copying.
Each of these buffs requires some further analysis to really get to the core of what Spark Double is offering.