Hearthpwn

Ok, im sure some people already knows it, but i think it's not bad to spread the rumor about this interaction.

So, let'say that druid just played living mana and has seven 2/2 on the board. You have Blackguard and TrueSilverChampion. With an incredible amount of luck (1 chance out of 5040 if i computed it right, so 0.019%~) you could clear completely the board and heal yourself for 14 without even attacking. True Silver Champion heals you before you attack. Right after that Blackguard triggers, dealing 2 DMG to a random enemy. If the random enemy was the same that you selected as attack target, it will die,so the attack will be canceled,TrueSilverChampion will not lose durability , and you'll be able to select a new attack target. So, you have a chance out of 7 to kill an enemy for free, one out of 42 to kill 2 enemies, one out  210 to kill 3 and so on, until one out of 5040 to kill the whole board. Of course you need to have 16 or less hp, since Blackguard will not trigger if your hero had full life. Is this something they will fix or is intended to be this way? Dunno, but in the meantime have fun messing around with this combo

It's intended.

There is a "proposed attack event" before the attack takes place. In this case, it's the healing, which in turn calls the Blackguard effect, both of which resolve before the attack.

If the defender becomes invalid (in this case, by being marked for death), the attack does not take place.

After-attack events (including durability loss and un-readying the hero) do not happen if the attack is canceled.

I have seen one guy using that tactic against me in wild mode it looked fun but it didnt end well for him in the end. I might look into this aswell.