carrying on his will - booster box One Piece TCG: Sleeved Pack (OP-13) The Theme for the upcoming 3rd Anniversary is the Three Brothers OP-13 Carrying On His Will

and any other monster will do, as well

Eye of Nidhogg overwrites all previous effects that set the creature's base power and toughness to specific values

Ive also found RG can splash decently well, as landfall already creates an incentive to play a Prishe's Wanderings or two

Sacrifice Crown of Vigor: Enchanted creature and other creatures that share a creature type with it get +1/+1 until end of turn

Given that these cards are not standard distributions and require a high level of TCG knowledge (plus a position as a Pokemon TCG judge) to earn, they're probably the most difficult common card to get in the entire history of the Pokemon TCG