Several cards in Magic instruct you to choose a random card or permanent in play. Recent examples of cards with abilities like this would be Merfolk Spy and Surreal Memoir. It is important that when resolving these spells and abilities that the end result is actually random. Most often players will use a die and assign potential objects or cards a number, roll the die and have the appropriate card be affected. For example, if the defending player had three cards in hand when resolving Merfolk Spy’s triggered ability, that player could put his hand face down on the table and assign number to each card. If a six sided die is used, card A could be revealed if 1 or two is rolled, card B if 3 or 4 and so on.

if a die is not available, then it is possible to shuffle the hand and have someone choose a card. It is important to note that when a card is directly chosen by a player there is the possibility of the choice not being entirely random.