Sanguine Bond is bugged
Sanguine Bond doesn't deal all the damage that it should.
For example if I attack with various draining cards, that would usually heal me 4 hps, the opponent isn't getting those 4 points as damage, only 2.
I've noticed it when the healing from multiple sources happens too fast.
Ran into the same thing today. And would have won the match if it had worked properly!