It is the Damage Event, and the attacker is the world (index 0)...
Something like this:
Code:
#include <amxmodx>
public plugin_init()
{
register_event( "Damage", "Event_Damage", "b", "2=0" )
}
public Event_Damage( id )
{
new szUsername[32]
get_user_name( id, szUsername, 31 )
client_print( 0, print_chat, "%s hurt self!", szUsername )
return PLUGIN_CONTINUE
}