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When Zacian was released in Generation 8, it established itself as one of the most terrifying physical attackers around. It had everything you could want: an excellent base 130 attack, a great 138 base speed, allowing it to get the jump on almost everything, as well as great coverage options such as Crunch, Wild Charge, and Close Combat. Its ability, Intrepid Sword, was also broken as well, giving it a free +1 boost in attack just for entering the field. This Pokemon was already insane, so you can imagine how people reacted when this mon got even better by tranfsorming into Zacian-Crowned Forme. This Pokemon has base 170 attack, an eye-popping base 148 speed, it gained partial Steel typing (making it a Fairy-Steel type, which just happens to be the best defensive typing in the game, with only 2 weaknesses) and it gained considerable bulk as well. Eventually, players decided to sent it the way of Mega Rayquaza, and banned it to AG. Thankfully, base Zacian was way less broken......Wait! Turns out, base Zacian was just as broken as its Crowned Forme, and was banned shortly after.