#!/usr/bin/bash

xfce4-terminal --drop-down --hide-scrollbar --hide-menubar -x mocp & #run the toggle command
sleep 0.1 # wait for the window to come out
IDs=($(xdotool search --class xfce4-terminal)) # get the list of IDs returned by xdotool and convert it to array
xdotool windowactivate ${IDs[-1]} #focus the last one of the IDs (if this doesn't work try changing the -1 index)