These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Game Breaker: Movement Speed. Just Movement Speed. Don't invest any points in offense or defense and just go pure movement speed. It becomes a game of chance, but the odds are in your favor. The player with the highest movement can easily get the most items, and if they get the item required for victory, movement speed makes escaping from any confrontation thereafter a breeze.
Arguably, even in (indirect) combat, these guys shine because they can make the most use of traps. Drop them all over, save up a few good attack and defense cards, and you MIGHT just be able to steal the item from the player who gets it before.
The cruelest tactic a movement-invested hunter can apply if someone else gets the target item before them is to litter the path to the exit with traps, ending the road with the movement-invested hunter himself blocking the path. From here, they can employ a purely defensive strategy until the uber monster known only as GON appears and play a game of chicken for surrender of the item. This is because GON will head straight for the player holding the target item, and if GON is successful in killing that player, it is a huge loss for everyone.
The Amulet is an item that limits what you can roll on the standard 6-sided die to 3 or higher (and not just by turning every 1 or 2 into a 3—it actually gives you equal chances of rolling any number from 3 to 6). Since the standard die is rolled for a wide variety of events, this gives you a massive overall advantage. It significantly aids your movements around the board; enhances your ability to attack, defend, escape, and give chase in combat; and even ensures that flags will give you better bonuses and never trigger traps (which would happen if you rolled a 1 on the flag bonus).