So I am really not sure if this is a bug or not, but since I couldn’t come up with an explanation and a bug is a possible one, I am posting it here.
It has only happened once so far, but I had a turn today playing druid in standard where, at the start of my turn, I had two cards in my hand suddenly discounting themselves 1 mana. I think both were spells and I can’t recall if those were the only spells in my hand. I looked to see if the anomaly was the ’first spell cast each turn costs (1) less mana’ but no, the anomaly in place was ’Give +1 Health to a minion on the board at the beginning of each turn’. This happened at the same time I was receiving armor from that 2 mana card that gives 4 armor on your next turn. I don’t think it ever happened again but I was very confused. I guess it was good for me, but if it’s some sort of bug triggered by some interaction it might be worth investigating. Or it might just be something else entirely that I overlooked but I couldn’t find a reasonable explanation.
Actually I might have that game recorded on HSReplay so I will check that back. It definitely wasn’t the naga, I don’t run that in my deck. I was playing Tony Druid.