A Brief History Built upon the groundwork laid by MTGs original creator, Richard Garfield, Battle cards are an evolution of the scrapped Structures mechanic
The reason is that this strategy tends to just grind the game to a halt, and it doesnt really win
Flying I, II Destroy up to one target nonland permanent
Once again, dont forget that the shroud prevents your own spells and abilities from targeting the equipped creature
Not only does it allow you to play less lands in your deck while still hitting your land drops, but the two card combination of an end step March of the Multitudes, untap, and Flourish is going to be format defining
It still happens simultaneously in game rules, and thats why you wont lose, but Arena works in two steps