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It's got to be the computer analysis (game review). I know the "accuracy" can be misleading (I'll link my video to that topic below), but it's still an amazing feature that helps me quickly identify my blunders, so that I can use that as a starting point for my own analysis.
Other than the analysis tool, I probably the "Endgames" (drills) or unlimited Puzzle Rush the most.
It might help to display what one gets with which plan.

ADDED: That was sloppy, sorry folks. I should have cut off everything but the white. I won't correct it though because today, I've promised myself to be lazy. ![]()
Honestly none of them. Why pay for things you can get for free?
You tell me.
It might help to display what one gets with which plan.
ADDED: That was sloppy, sorry folks. I should have cut off everything but the white. I won't correct it though because today, I've promised myself to be lazy.
16 tabs is crazy