on ^*:TEXT:*:#chan1,#chan2,#chan3:{ if ((!close isin $strip($1-)) || ($nick == BADBOT)) { iline $badbot 1 $nick - $1- | haltdef } }
alias -l badbot { var %w = @badbot | if (!$window(%w)) { window -<insert your window parameters here> %w } | return %w }


If that doesnt work then, you likely have a another ON TEXT event that is displaying the bots/others messages in the channel.
If Thats the case its alot harder but not impossable to stop it displaying.