in the case of the card introduced in 500 Years In The Future , its a Trafalgar Law card thats being released as a Treasure Rare
Only two copies of the rarest Blastoise card exist
SOTHERA, THE SUPERVOID This seems specifically good against itself, and I can dig that
Special Summon that target, and if you do, immediately after this effect resolves, Synchro Summon 1 Synchro Monster that mentions a "Synchron" Tuner as material, using that monster and this card only
If you want to move into the land of Mythic Raredom, Lorthos, the Tidemaker can be a nice finisher, as well as Sphinx Ambassador, though Sphinx of Jwar Isle does have the all-important shroud (but then again, there are 20 counterspells in the deck)
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