magnetic card sleeves 20-Pack One Touch Sleeved-Card Magnetic-Holders These magnetic cardholders elevate the security and presentation of your trading card collection 35pt. Magnetic One Touch Card

The good news is that protecting your cards is straightforward and doesn't have to be expensive

I'd grab a pen and have some paper handy to write on so that if you need to make notes about things that are harder to track because they aren't as visible ("Okay, I have his Teferi's Protection exiled with my Spelljack" or "Erin's graveyard contains three cards she can cast from the graveyard"), you have easy access to doing so

Especially if one has looked for a card for years

There are sideboard cards relevant to the matchup in each format since affinity is a deck usually played in Pauper, Modern, and Legacy

Jigglypuff is no slouch either, using the Lullaby attack to put the opponents active Pokmon to Sleep can buy precious turns while trying to build up your boardstate

It can stop a Battle Phase, negate a summon, or Omni-negate any effect, all while banishing itself so that your opponent can't try to take care of it after baiting out its effect