Since it's a stock, you can easily open the include which contains the stock to see what it does and if that fits your need.
I found this in message_stocks.inc, don't know why yours say engine_stocks.inc.
Code:
/* Kills a user without a message. */
stock user_silentkill(index)
{
static msgid = 0;
new msgblock;
if (!msgid)
{
msgid = get_user_msgid("DeathMsg");
}
msgblock = get_msg_block(msgid);
set_msg_block(msgid, BLOCK_ONCE);
user_kill(index, 1);
set_msg_block(msgid, msgblock);
return 1;
}
As far as I see, it is not resetting the kills but I don't really know if user_kill() removes one.
You'll just have to try it out to make sure.
The second parameter of user_kill() prevents the score from changing.
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