And a really deep customization system of cards and weapon types that can make possible a diverse amount of possibilities, two player who play the same characters could play them in very different ways and their iterations and effect on the battlefield could be very different.
Also, what a breath of fresh air in the world of hero shooters. All of them are T for Teen and this one is rated M and isn't another Pixar game that cucks to Feminism and the Anita Sarkesian cult. Heroic men can be muscular and badass, heroic women can be sexy and athletic, it's ok to not be unhealthy.
And who doesn't love Mad max, Borderlands, gorillaz, Gears of War, brawler games with a dash of anime? The style and aesthetics is actually what drew me in and away from Overwatch.
And in a world predominated by mindless Battle royales and PvP it's nice to have some multi-player PvE with actual meaning, direction and story-line implemented into the game mechanics. It's definitely not a game for normies who play CoD and Paladins.
EDIT: i'd like to remind all of the detractors of the game also; MSE really do listen and make updates heavily based on community feedback. This is historically evident. They may not do it as fast as a HUGE developer, but they do it.