Some of the fights after 5 out of 8 or sometimes even 3 out of 5 REQUIRE massive RNG in order to have a chance, because even if you get a good Mulligan and even if you do no technical mistakes at any point you STILL can die several times in a row because of the randomness of the draw.
Randomness should play a role but it is ludicrous on a single-player solo adventure which is there mostly for the story; also maybe I underestimate how much RNG plays a role on PvP too; I hope it’s not that massive and I haven’t realized it because on single-player it’s obvious no mistakes were made by the player when they lose by RNG multiple times in a row (on some fights).
PS A ludicrous example I just noticed is that on the Druid mercenary adventure at around ~5/8 there’s an enemy who is supposedly a human paladin and they have a gimmick of having a spam of secrets that basically ruins your minions whenever they attack. Well: the fight appears to have an anti-gimmick because you can get cards on your deck that mind-control his minions so logically that might counter his secrets right(?) and that’s a smart thing to do that most players might miss right? WRONG: you still can die several times in a row due to RNG because the mind-control cards are few lol (so you don’t even get a chance to have a counter of the gimmick lol…)…