Pick systems like a game room. None selected means every system. Each choice of systems keeps its own best.
Every single-player case you finish (Daily, Infinite and custom sets) gets a score out of 100 for how much of the list you named. Naming 40% of a list earns full marks, and Rare, Deep cut and Zebra answers count one and a half times. A system's strength is the average of its last 10 cases. Systems need 3 cases before they're ranked.
Collect the presentations you want to drill. Play them on your own here, or pick a set in a game room's settings to play it with friends.
Every past daily dive, with the same 7 cases everyone got that day. Days you've played show your depth and level; open one to review its answer keys or replay it unscored. Unplayed days count when you play them.