On voice
From Scriptwiki
The on VOICE event triggers when a user on a channel is voiced.
on <level>:VOICE:<#[,#]>:<commands>
$vnick refers to the user who was voiced.
Example
Triggers when a user with level 999 was voiced in #help.script or #mIRC and devoices him again:
on 999:VOICE:#help.script,#mIRC: { mode $chan -v $vnick }
See Also
On devoice triggers when a user was devoiced.