Niantic has teased that Pokemon GO players will soon have the chance to get yet another Master Ball. Like in all other Pokemon games, Master Balls are the best Poke Balls in Pokemon GO.
Pokemon GO players can guarantee a catch whenever they use a Master Ball, but the downside is that Master Balls are in short supply.
In fact, Pokemon GO players have only ever had the chance to add two Master Balls to their item bag since they were introduced to the game.
So far, Pokemon GO players have had two opportunities to get Master Balls. The first was through completing the Let's GO! Special Research quest, and the second was by completing the Timed Investigation: Master Ball quest or Special Research: Master Ball, for those that didn't complete the Timed Investigation fast enough.
Now it seems a third Master Ball is on the way to Pokemon GO, but it remains to be seen exactly how players will unlock it. Niantic recently took to Twitter to release a new teaser video for Pokemon GO that shows a Master Ball and offers little else in the way of additional context or details.