Basically, it's like your opponent (assuming you cast it during your opponent's turn, which is usually correct) just randomly decided to say "go," right in the middle of doing cool things
Sometimes supposedly overpowered cards end up being a bust
Fly high with the best card in the set Rayquaza VMAX with 210HP, and no weakness as it is a dragon-type, and other great cards such as Duraludon VMAX with 330HP and ability that prevents all damage done to this Pokemon by attacks from each of your opponents Pokemon that has a special Energy attached to it, Noivern V, Dragonite V and more
It's a powerful tool for card advantage in three mana fused, and unlike most split cards, you aren't losing mana for each half or speed like Assault // Battery
In fact, negativity only seemed to arise around Magnifying Glass, which was deemed painfully generic by some players