Copying spells inherently has one of the highest ceilings a deck can have, however there will be games in which your instant won't do much even if it is doubled up
[EFFECT] Negate that attack
(2) You can destroy 1 card you control: Special Summon 1 "Thief of Heart" Monster from your Deck, but its effects are negated
Manufacturer Logo and Air Holes: The plastic wrap on a genuine box must contain a small, white logo of The Pokmon Company embedded within it
In the manga Dark Yugi is surprised to see him in Battle City, since up to that point there was no indication that Dark Bakura knew much about Duel Monsters, but he proves himself a formidable opponent and pushes Yugi to the brink of defeat before he summons his God Card
Trade Secrets Banned in Commander, Trade Secrets could just give two players their decks plus a Reliquary Tower in hand leaving everyone else behind if your chosen opponent engages the may clause at warp factor 10