Tech Choices and Side Deck Tech choices are cards included in your deck specifically to counter certain strategies or popular decks in the metagame
This is why games like this are successful
Azorius Control: A classic control strategy relying on counterspells, board wipes (e.g., Supreme Verdict), and planeswalkers like Teferi, Hero of Dominaria to dictate the pace of the game and eventually win through overwhelming card advantage or an unassailable board state
Maintaining the Scarlet & Violet example, a regular Booster Pack from that collection has a pull ratio of 4 common cards, 3 uncommon cards, and 3 foil cards (at least one of which will be rare, ultra, secret, or, hyper rare)
For instance, many stores host a variety of events, from competitive tournaments to casual meetups