This event is unlocked after you complete the preliminary round of C Rank ninja tournament. To begin the quest, go to the tunnel on the right side (looking from the entrance to the cave, from the beach) - the same tunnel through which you were travelling to start the "Basking in the Limelight" event. You will stumble upon a 4-man group of ninja. Speak with whoever you want with to learn about the task.
It's rather simple - you have to defeat an enemy called Bee nasty. He will be using his awakening - in the "regular" version he won't be a threat at all. After he's activated the awakening, all you have to do is to stall him for several seconds until he runs out of chakra, which should give you an edge. Don't let the enemy prolong the encounter and fill his True Awakening bar - if that happens, he will become much more dangerous. Bee is quite weak, so you shouldn't have any problems with defeating him.
After you've completed this encounter, after a short conversation, Bee will flee and you will have to find him inside the cave. You have to jump to the lower level of the cave - this level is very small, so you should locate him in a matter of seconds. Start a conversation with the enemy, after which another, identical fight will begin. Defeat him once more, after which both of you will be teleported back to the rest of the group, which gave you the task.
The quest will be finished. You will be given:
- 4000 ryo
- 2x Rain of Kunai
- Ninja World Tournament allies: Bee Nasty, Ei, Third Raikage, Darui.