I’m sure it’s a bug because heroic difficulty in the new solo adventure offer no challange above normal. no new cards, no new abilities, no smarter play.
rng can make heroic much easier than normal. I’m sertain it’s a bug, you forgot to trigger the “heroic” functions.
Well I cruised through the regular and have been bodied by the 5th or 6th boss every time in heroic.
This is my experience too. My runs, both normal and anomaly, are pretty straight forward and I finish them consistently. In heroic I wasn’t able get past boss 5. Only two tries though, maybe not a big enough sample.
how do I even activate heroic?
I’m sure I could stomp everyone casually then feel pity for myself as the whole adventure felt like an easier K&C (at least so far, at some point I started smorking like hell every boss, my best was a turn 4 lethal against the 5th boss), or I could get beat solely by uncouterable RNG and ragequit like a baby
Pfff… amateur… here’s how I finished a T1… The card in hand was the T2 draw. 
https://imgur.com/a/HD7BNQp
Nah, the different bosses’ decks are much better, HPs are stronger (and udually auto-cast), and the AI is smarter and punishes misplays VERY hard. Heroic definitely stands up for its name imo
On normal difficulty, I have so far completed every run I started. First wing four times (each of the Mage starting decks, with each Hero Power used once and one used twice); second wing twice (Shaman and Hunter each once). Had a few times where I had to take care but most of them were fairly easy.
On heroic, I tried just a single Mage run in the first wing so far. Thought to myself that it was fairly easy for the first four bosses, had to reconsider that assessment at the fifth, and got absolutely slaughtered by the sixth, despite having rewards and cards that felt like a very good combo.
Based on this admittedly too small sample, I’d say that Heroic is doable at my skill, but requires some luck with cards, rewards, and bosses; whereas Normal runs will mostly go to 8 for someone at my skill level unless unlucky.
I definitely think Heroic is easier than previous incarnations of the same, but at the same time, it’s still not something that you can just breeze through with very little thought. I have completed the first wing on Heroic twice now, but it took me a good 7-8 tries each time. You can put together some ridiculous decks but it only takes one boss to stop you in your tracks
i have not played for the past week that much but my first impression upon completing the heroic modes was indeed that i questioned if there was a difference between normal and heroic.
you have a lot of freedom with plays you can make in the solo adventures each turn and i like it since i can experiment with mechanics i have never been able to do before.
lets say if you want it to be hard then you need to be unlucky i guess ?
or pick some bad cards in between your picks.
If you are looking for a challenge, do Mage Heroic in first chapter and choose Frostburn hero power and random mage deck.