In terms of what new mechanics are introduced, the fights with the Jarls and the wounds suffered in those battles are the two biggest tweaks to the original gameplay
There are Shop Tokens, there are Hourglass, there are Tickets and there are Emblems - it's all there, but as far as I can tell, you can only buy one of these, and while it's technically possible, it's not exactly front and centre in the interface
Wiglett and Wugtrio the latter preventing your opponent from retreating with its attack provide reasonable support
It really helps that the reward of Marchesa, Resolute Monarch has one of the rarest effects in all of Magic in being able to remove all counters from a permanent
The "at the time" buffs which are your Giant Growth cards and your Curiosities
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