Basically Frantic 2 but way worse. Insanely low reload rate and slow bullet speed makes me want to rip my hair out. The lag spikes every 3 seconds make the game almost unplayable during bosses. 2/5
The real win rate for cards is about 20-25%, not the oft-mentioned 40%, which means you need to grind out more like 40-50 wins, not 20, before you get your 10 cards. A new player is unlikely to be able to beat the metadeck with an all random deck, and about everyone SR20 or higher plays some variation of the metadeck.
In other words, in trying for those 40-50 wins, you're going to end up losing as many or even more games than you win. All of a sudden you're looking at a 100-150 game investment @ 5-10 min a game just to get your 10 cards.
If they want to grow the community, either bring back 3 challenges a week or seriously bump up the win rate. The status quo is just too crushingly against new players to attract that many to stay.