Sometimes itll be letters, sometimes itll be numbers, and other times you may have symbols, or even a combination of the above, to identify which set a card is from in any given TCG
Most card games do that and it generally makes for better-rounded decks
Pop this song card in with an amethyst deck filled with Merlin and watch it go to work
Recently, however, the price of these cards has absolutely exploded, jumping by over $360 in one instance
That ability keeps your options wide open, whether its removal like Fatal Push, disruption with Counterspell, or efficient value from Ponder
Rather than challenging your opponent directly, the game plan is to get more value from your board than your opponent can from theirs, faster - while also using tricks to disrupt them and Bodyguards to protect your more important characters