Q: Can I trade with another player?
A: No. Players can never trade with each other.(Magic casters are a suspicious lot who don't trust each other. They are also pack rats by nature and will never part with an item unless forced to drop it.)
Q: Can I pick up a dropped item?
A: No. If a player is forced to drop an item, that item is lost.
Q: Instead of casting "Luck" (Ignore land card and draw another) on myself can I cast it on another player to force them to ignore a good card?
A: No. Players can only cast spells during their own turn. (... but I do like the nasty way your mind works....)
Q: Can I buy Healing potions from the Store for 50 gold and sell them to the Trader for 100 gold and then loop this to make lots of gold?
A: Yes.(I have no problem with a player working for their gold).
Q: If a thief steals my Shard belt can I remove the shards first?
A: No. Once shards are placed in the belt they cannot be removed.