Assuming g_bHasKnife[] is the bool for if the player has bloody knife.
PHP Code:
public FwdPlayerDamage(victim, inflictor, attacker, Float:damage, damagebits)
{
if(inflictor == attacker
&& attacker != victim
&& g_bHasKnife[ attacker ]
&& is_user_alive(attacker)
&& get_user_weapon(attacker) == CSW_KNIFE )
{
SetHamParamFloat(4, damage * 3.0);
}
}
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