Alphabet - including special symbols, more on that later This means the first box on the shelf will be white common creatures starting with the letter A all the way up to Z, after which youll find white common enchantments, instants, sorceries, artifacts and planeswalkers, all alphabetized
(If a creature with a shield counter would be dealt damage or destroyed, remove a shield counter from it instead.) Shield counters don't prevent players from sacrificing creatures
This means that, while you'll likely never be able to buy the great Human tribal Commander Rick, Steadfast Leader ever again, you'll be able to buy a card with an in-Magic-universe flavour that does the exact same thing and is treated as the same card in terms of deckbuilding limitations
This might explain why it's banned in basically every format you can think of