We were starting to have discussions of what came after the Bolas Arc (the three-year stint from Kaladesh to War of the Spark ) and were exploring what new worlds we could visit
Tyranitar and Carnivine's abilities make their attacks do more damage, Magnezone and Raichu's cause them to take less damage, and Heatran and Rotom's removes their retreat cost
As its a noncreature spell, its also a great one mana choice for all manner of decks running Commanders from Strixhaven and Marvel Super Heroes too
C Common Thunder Hand X LIGHT Level 4 [ ThunderEffect ] ATK 1600 DEF 1600 If a face-up monster(s) you control with 1600 original ATK or DEF is destroyed by battle or an opponent's card effect and sent to the GY, while this card is in your hand or GY: You can Special Summon this card (but banish it when it leaves the field), and if you do, destroy 1 card your opponent controls
While its a level four monster with 1800 attack and 400 defense, in order to attack you have to tribute a water type monster, attacking three times in each battle phase
Instead of just limiting a card to only one copy per deck, they forbid the usage of certain cards entirely