At begining, someone throw a grenade to a user, and that user should throw the grenade to someone else before it explodes.
Each person that post should count down the time before the grenade explodes.
The count starts at 5, and if it gets to 0, the user with the grenade dies.
example: i throw you a grenade and i count 5
then if you want to survive you should throw it to someone else and to count 4
