The snippet section is to post full working snippets, not to ask for help to fix it.
If you need help to fix it or to get it done an working then you should have posted it in the forum.
@
mIRC Snippet Requests
or @
mIRC Scripting

anyways just as an example.

on @*:text:!steal all:#:msg # This is a test. This message means he $iif($r(1,100) < 21,stole all.,failed to steal.)

<~napa182> !steal all
<~Sick0> This is a test. This message means he stole all.
<~napa182> !steal all
<~Sick0> This is a test. This message means he failed to steal.