For just one mana, Gideon's Sacrifice redirect all damage dealt to us to one of our creatures
It resolves even if that spell or ability is countered or otherwise leaves the stack without resolving
Its strong, its a shell for the nine, and it gives you a strong combat win condition in Dimir, which it has been crying out for
Upon investigation, it was discovered that one of the player's cards ( Time Walk , which is still a massive Game-Breaker and one of the Power Nine, but isn't an instant win on its own) read, 'When this card is played, opponent loses next turn' (as in, 'the opponent skips his next turn'), but the player interpreted the text to mean 'the opponent loses the match next turn' and had been using that inadvertent loophole as an instant-win condition
You can splash out on a foil variant for one of your favourites, maybe your commander, and you can find cheap, battered versions of cards you want in your deck that you dont care about as much
Trainers build a deck with a combination of Pokmon, Energy, and Trainer cards, strategically selecting cards that complement each other