You do it with each character that gets to icewind dale, the artifact will then be available at the rewards claim agent in PE for any other characters, thus you do it once and any new character can stop by and grab the DC artifact, do it on a TR and you can grab the TR artifact also
There's not really a ton of poll options, but as I prefer unique and creative maps, I chose the first option. More accurately if you just use 1 pre-fab map, pop a few encounters and details in, you likely wont get a good review from me, especially if your details aren't aligned right (chains popping up from the floor below…