rare pokemon cards psa 10 N's Reshiram #109 Battle Partners SV9 Japanese card – GorillaTCG Captured in a crystal Mewtwo VSTAR (79) (Secret) 79/78

Not only does this prevent your opponent from XYZ summoning next turn, but you can use these materials for your own summon

The Vancouver mulligan The 2015 Magic Origins Pro Tour in Vancouver introduced (you guessed it) the Vancouver mulligan

Dragonite ex can be obtained from Eevee Grove Booster Pack in the Eevee Grove Set

it costs 1 mana less, makes more impactful tokens, and is generally a very annoying spell, in the best ways possible

You could forego a copy of Reset Stamp and Tag Call to include 2 of these though, as they might also be helpful in the mirror match

You cant flood with this in your graveyard, which is quite nice