Voted for Marco, his was definitely the "brightest" of the bunch. But they weren't bad at all. Though I do have some things to say on a couple:
Theryan: Anything non-Classic plopped into the Classic Tileset immediately becomes out of place, unless it is stylized to fit Classic's graphical style. That said, those GB bushes must DIE [/CDI Zelda Reference].
William: Custom tileset, eh? Reminds me of the Happy Set

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Alison: That boulder looks horrifically out of place. As if it's just floating above the lava, instead of actually in it forming a bridge. To remedy this, edit it so it appears as if it's submerged within the liquid. Of course, with the space you left open up there, Link could just shimmy around the gap altogether

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