I have been an avid (casual) player of hearthstone since its initial release. While I have played my share of games, I have never bothered to delve deeper into the mechanics of the game.
After watching several hearthstone videos on youtube, I came across the term "order of play". It seems to be somewhat related to the order of which abilities like deathrattle are triggered being determined by the order in which the minions were summoned.
Take for example a situation where a Dreadsteed is pit against am Unstable Ghoul. Supposing the unstable ghoul is left with one health and it was played first, if you were to use Whirlwind as a warrior, would Dreadsteed die once or twice?
I am certain that there are better examples than this but I can't seem to think of one as of right now. Perhaps you can provide an example in your answer.