this happened to me on my second boss. im not sure if that was a bug but this is what support sent:
Dear player,
Thank you for your understand.
When you see a boss during your adventure, you will be asked to choose between accept and ignore. If you choose to ignore the boss, you can proceed your adventure and challenge the boss later; if you choose to accept, you will enter a fight with the boss immediately. There are not much differences between two choices.
All of your pals can attack the boss you found. And after the boss is defeated, three of you will get gems for reward:
1 One for the person who found the boss.
2 One for the person who caused the most damages.
3 One for the person who got the last shot.
According to your description, I think that your pals defeated the boss before you ended the adventure.
Did you get the gem for finding this boss?
Regards,
Elle
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I'm not sure if you will find the answer there. But since I lost that boss I always finish the map first. So I use a resurrect card after encountering a boss and since then it always ends up in the boss raid activity. Hope that helps bossing
