GadgetJax
Traveling Storyteller and Card Faker
I think the reason why everything will be nice for XY-on is because every strong EX deck loses at least 1 or more tools that made it so dominant.
-Yveltal EX loses Darkrai EX, Garbodor, and LaserBank.
-Mega Kanga and Gardy EX drop Max Potion.
-Seismitoad EX loses LaserBank, Crushing Hammer (unless it becomes KSS-on), Reshiram, Garbodor, and more.
-Fighting decks lose Terrakion and Landorus-EX. Bye bye T1 donks from LandoBats!
-Gengar EX loses Zekrom & Sigilyph.
-Dialga EX and Mega Aggron EX lose Keldeo EX with Float Stone.
-Camerupt EX loses Emboar, though I do think that Magmarupt works well.
-Primal Kyogre EX loses Manaphy from Plasma Storm along with Keldeo EX with Float Stone. I've tried Lapras with Trick Coin and it is a tiny bit better because of the extra HP, but it lacks Final Wish.
-I can't think of anything specific that Primal Groudon EX loses, though.
-Yveltal EX loses Darkrai EX, Garbodor, and LaserBank.
-Mega Kanga and Gardy EX drop Max Potion.
-Seismitoad EX loses LaserBank, Crushing Hammer (unless it becomes KSS-on), Reshiram, Garbodor, and more.
-Fighting decks lose Terrakion and Landorus-EX. Bye bye T1 donks from LandoBats!
-Gengar EX loses Zekrom & Sigilyph.
-Dialga EX and Mega Aggron EX lose Keldeo EX with Float Stone.
-Camerupt EX loses Emboar, though I do think that Magmarupt works well.
-Primal Kyogre EX loses Manaphy from Plasma Storm along with Keldeo EX with Float Stone. I've tried Lapras with Trick Coin and it is a tiny bit better because of the extra HP, but it lacks Final Wish.
-I can't think of anything specific that Primal Groudon EX loses, though.