The easiest way to describe it, for me, is the idea that you managed to achieve an advantage by forcing an opponent to react to your game plan in a way that loses them card advantage or tempo
Not only does it contain the best deck in the game (Mewtwo EX), it gives a wide range of strong cards that can get you a solid footing as you start the game
FAQ What Is The Strongest Pokmon Card
Familiars: +4 Pyroblast +1 Nihil Spellbomb -1 Makeshift Munitions -2 Sewer-Velliance Cam -1 Toxin Analysis Red Rally: +4 Hydro -2 Sewer-Velliance Cam -2 Nihil Spellbomb BG Spy: +1 Nihil Spellbomb +2 Envelop +1 Faerie Macabre +2 Cast Down -1 Sewer-Velliance Cam -1 Makeshift Munitions -4 Refurbished Familiar Thanks to Team Wizards Cottage for helping me understand and tune the deck
Some very good reprints are combined with a clear plan to create clues, draw cards, and profit
The difficulty curve is insanely steep, the only way to stand a chance is to grind, and there's probably more grinding in this game than the GBA's Reshef of Destruction, although that game hasn't gotten a speedrun yet