Shyster's Shell Game (5e Equipment)
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Wondrous Item, uncommon
A set of 4 cups and a small ball. Each cup has a sigil on the outside of its base, and may contain up to 1" by 1" of object(s). When someone touches the sigils of two cups, the contents of those cups swap places.
These are commonly used to scam people. When running a shell game, you may keep one of the cups hidden on your person or within reach. You must make a Dexterity (Sleight of Hand) check, contested by the Wisdom (Perception) of the individual playing the shell game, to teleport items between this hidden cup and the other three cups. You don't need to make this check to teleport the contents between the three visible cups while you are moving them. If the ball ends up in one of the visible cups, the individual playing must make a DC 15 roll (no modifiers) to win, though you may still teleport the contents of the cups by making a Dexterity (Sleight of Hand) check, contested by the Wisdom (Perception) of the individual playing.
An individual may identify the magical properties of these cups by examining at least two of them for 10 minutes, by succeeding a DC 15 Intelligence (Arcana) check, or by using a spell such as Identify.