So this is a similar game where you collect cards that you use to battle and you level them up by playing different levels (which is better then putting in thousands of 1-2 stars)
Anyways my main point is that games DISCLOSES their pack chances (which are basicallly summons in this game)
Shows the chances of getting that character so people can decide if it’s worth spending their hard earned credits and so people are not disappointed if they don’t get it.
This is also why this game is 8 years old and is still getting frequent updates.
TLDR; disclose your summon chances, it’s better for everyone