The Merfolk archetype has plenty of synergies, especially involving Islandwalk, which makes your creatures unblockable if your opponent controls an island
If you are playing a deck that can effectively get a key combo piece into the graveyard via something like a discard or counterspell, following up with Surgical can end the gamefor example, against Ad Nauseam
Card [Usopp Gold] Premium Booster 2 Uso-Hachi [SP] Royal Blood [Japanese] ST18-001 Usopp [Playmat Limited Edition] Promo [Japanese] OP10-042 Usopp [Alt Art] Extra Booster Anime 25th Collection EB02-022 Usopp [Leader Parallel] Royal Blood OP10-042 Sogeking [Alt Art] Pillars of Strength OP03-122 DON
Unlocking all of the Promo-A cards is proving difficult but this Mewtwo one is taking the biscuit
Instead, when it comes to Un-set rares and mythics, demand seems to be primarily based around how funny the joke is, followed by weird, fringe factors