Eeveelutions have completely barreled through this year thanks to being a prominent part of Evolving Skies, so it's fitting to see one rise to the top of this list.
The plane of Dominaria was the birthplace of the shadow mechanic, so maybe well see shadow again on a return visit, but its a fairly small possibility because R&D avoids putting parasitic mechanics (i.e., mechanics that only work with themselves) in modern sets
Lunala 57 Pikachu Lightning 60 Tail Smack (30) Solgaleo 58 Alolan Raichu ex Lightning 140 Psychic (60+) This attack does 30 more damage for each energy attached to your opponent's active Pokmon
It sniffs and snuffles around, looking at the long faces of the Magic players who were promised that Magic 2010 would be a set with all new cards, only to find out that many of them were merely renamed cards such as Runeclaw Bear and Divination
This is due to its effect, which states that your opponent cant attack this monster while there is another Pyro monster on the field