on rightclick holding diamond:
set {centhe2.skill.%player%} to 1
set {centhe2.click.%player%} to now
wait 15 seconds
difference between now and {centhe2.click.%player%} > 14 seconds
set {centhe2.skill.%player%} to 0
on damage:
if 1 = {centhe2.skill.%attacker%}:
make attacker damage victim by 5