What custom Magic cards usually means (so you dont overcomplicate it) Most people making custom Magic: The Gathering cards fall into one of these buckets: Alt-art re-skins: Same card text, different art and vibe (your Sol Ring is now a cursed waffle iron, as it should be)
It's inferior compared to Swift Response, but it does trigger Vega and pump up Alrund while in exile, so it's always worth considering
Then if the creature you gave the counter to is sufficiently large, specifically power 7 or greater, this creature becomes prepared
Theres lots of good nonlegendary goblins to copy, and with the choice between removal, a temporary mass haste enabler, or an ability that hopefully adds some goblins to your hand, theres lots of potential combinations
Beyond the 151 Pokemon, there are 14 trainer cards, 16 illustration rares, 16 full arts, seven special illustration rares, and three gold, or hyper rare cards