Thoughtseize
Although Thoughtseize was not included in the sets of Amonkhet or Hour of Devastation proper, instead being elected as an Amonkhet Invocation, Thoughtseize is a remarkably-impactful card in so many formats that Wizards of the Coast must have had the thought process of "Hey, why not?"
As such, we will see Thoughtseize in basically every Historic deck that utilizes[...]
