Mark not being able to change makes creating skeletons much harder: pends no longer allow for flexibility in element of added cards
I agree and feel I would prefer if the Mark was flexible.
It would allow for more flexibility in what you do with the skeleton decks.
For example:
I may build a mono
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deck thinking Lava Golems, so I'd choose
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Mark. Now no-one can choose any other
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monster unless they want to waste all of their quanta. Alternatively I could choose the
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Mark, but then it would be impossible to play Golems. By leaving the mark flexible, there's a greater chance of originality between same-skeleton decks.
One other question, just to be 100% clear:
Must the 6 cards you choose be 6 of the same card?