How it works
Every seconds some ninja will spawn (depending of the number of player on the map), the first to click on them will get a reward and will have to wait before being able to get another reward.
To launch it, you can go it by hand or Auto start it with OnClockXXXX. The players will join using @ninja.
You can edit the number of ninja, the timing between spawn, the delay between rewards ect. Follow the !!Modify
With a small number of ninja spawning, only the fastest will get rewarded, if you spawn a lot of ninja, everybody will get a chance to have one!
There's more information to help the configuration inside the npc.