I made a huge mistake by playing duels

Are Duels some sort of a joke?
I made a mistake to go and try Duels and got 3 DKs in a row that devastated me. Had no chance to do anything litteral steamroll.

Blizzard sure knows how to make a warm welcome to a player.

The opponents you face are totally random, and Death Knights is just another class in Duels. Not something that should cause you grief.

It all depends on your starter deck, your playing style.You may have just been unlucky.

Try playing Casual Duels before doing Heroic. Casual Duels is also challenging but will not cost you Gold.
Bomb Warrior is the easiest to play, if you’re new to Duels.

You made a mistake by playing this dumpster on fire but that’s another story.

It was casual that was my gripe, I was trying to get a feel for the game but just got steamrolled.

Definitely play Bomb Warrior to get a feel for the mode.
It’s the easiest to build-just take cards that generate Armor, and watch the opposition crumble.
People are playing with strong starter decks in Duels regardless of mode.

The reason i think why you find yourself here is because you expected it to be like normal hearthstone. Duels is an entirely new breed of hearthstone and unless you are going to understand how it works, will not win anything.

Firstly decks do not have double copies of cards meaning a card will be harder to have at certain time. Secondly decks like this usually going to be some sort of combo or fast lethal tactic they need to pull off. Same as hearthstone tho remember that Combo, Agro and control. Aka Rock, paper scissor game. Figure out what type of deck you are losing against and build either a deck to counter it or that can beat it.