The word original in the original text is used in the sense of "from or in the beginning; at first", while you seem to be taking it in the sense of "in a novel and inventive way".
The phrase "originally devised" implies the usage of the devised thing has since changed or expanded beyond the purpose of its invention. This is important, because it is in a passage talking about one of those new usages - dungeon generation.
Yes, your sentence has the same meaning, and in a weak sense has the same implication, but "originally devised/invented" has a history that boosts that implication to make the purpose clearer.
The phrase "originally devised" implies the usage of the devised thing has since changed or expanded beyond the purpose of its invention. This is important, because it is in a passage talking about one of those new usages - dungeon generation.
Yes, your sentence has the same meaning, and in a weak sense has the same implication, but "originally devised/invented" has a history that boosts that implication to make the purpose clearer.