Just brainstomring here...
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Pocket of the Void: Immune to pickpocketing
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Shrunken Head: All players in your hex and all neighboring hexes receive -1 action point.
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Tainted dagger: The next opponent you defeat must discard one card per round until he rests (takes no action) for a round.
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Aetherial Forge: Armorsmithing requires no cards this turn.
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Marble: Winner of your next duel discards instead of salvaging. Loser salvages instead of discarding. You must disclose your marbling prior to deckbuilding.
Hex: (homonym ftw!) All players in your hex and all neighboring hexes move 1 hex in a random direction.
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Master's Tools: Doubles weapon cards created during Weaponsmith ability use during one turn. After use, Master's Tools become regular tools.
Dragon Egg: Destroy for one Ruby Dragon. If you drop down to 10 HP or less at any point during the following duel, you lose that duel.
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Concussive orb: Collapse a mine hex, turning it into a mountain or hill hex. Players in the mine are immediately transported to a tunnel exit of their choice.
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Padded Moccasins: Immune to aggressive attack while in a forest hex.
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Bale of Hay (no srsly): Doubles speed of White Stallion for two rounds. White Stallion may not be used the following two rounds.
Irradiation Crystal: Reveals anything hidden in your current hex and all surrounding hexes.
Prsim: Convert six Light cards to six non-Light, non-rare card of your choosing. Card types must match.
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Two-Headed Coin: Destroy the coin. All players of your element receive double resource income this turn.
Egg of Fate: If you use 6 fate eggs in the next battle and win, salvage all of your opponent's cards.
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Telescope: Doubles the effectiveness of Treasure Hunting and Trade Routes for three turns.
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Rainbow Cape: You may use any mark in battle for the six turns after you receive the cape. Plus you look like a pimp.
Will try to add more later. This was actually a lot of fun. I recommend more people propose ridiculous items.