Three of Coins

Three of Coins is a consumable that, when used, provides a chance that a Guardian will receive an exotic engram after killing an Ultra or completing a Crucible match. If an exotic engram is not dropped, the Guardian can use another Three of Coins, and the chance that the next Ultra killed or Crucible match completed will yield an exotic engram increases.

Chances
Player trials show no increase in odds of obtaining an exotic engram when consuming multiple Three of Coins before the buff is consumed; therefore, optimal usage is one Three of Coins per Ultra kill or Crucible match. The following table illustrates an analysis of the odds of obtaining an exotic after consecutive Three of Coins consumptions:

Trivia

 * Certain ultras, such as Omnigul and the Psion Flayers in the Dust Palace strike, will never drop exotic engrams regardless of whether or not the player has used a Three of Coins.
 * There is a hidden cooldown period after using a Three during which using additional Threes will not increase drop chance in order to prevent exploitation of easily repeatable ultra kills.