The best way to farm prophetic is accumulate points in lvl 10 gate of satorious then farm the prophetic. You can level your characters as well and farm him at the same time
Yeah, I usually farm him in 40 until I get all event points, then I just farm him x3 on lvl 10, it helped me lvl up Hassleberry and Yubel to 45, I haven't missed a single card reward ever since I started doing that. :3
Brick proof
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