Challenge Event Heroes have a chance to be obtained from the Event Summon Gate during Challenge Events, which are held over five days every month following a regular rotation. A number of distinct Challenge Events, each with a different group of Heroes, form this rotation. Challenge Coins can be earned in Challenge Events to make free Event Summons.
Please note that Event Summon Gates can also summon Classic Heroes. One exception to this is the Challenge Festival Summon, which does not summon Classic Heroes.
You can always check the exact probabilities by tapping the blue circle icon with an "(i)" in the top left corner.
- Information on other kinds of Heroes can be found here.