That’s… absolutely not true. Now I haven’t played Yugioh in a loooonng time, but from I can recall, there were setups that let you flat out win on turn 2. Hearthstone doesn’t have any OTK combos that don’t require previous setup, not since the Patron days. The closest would either be Velen + Embrace The Shadows + heal -> damage spam, but that requires Velen to be alive for a turn or a lot of ET ticks. Still not a perfect OTK.
That being said, Duelyst doesn’t have many OTK combos either, assuming we’re going with the standard definition of OTK as “Killing an enemy in one turn when they have 80% or more of their max health.” Theres Divine Bond + Ironcliff, which is already a known problem. And that’s really it. Even Shadow Nova is just burst damage.

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