You want to ride with someone but that person is not available. So then you have the option of bringing a bot that will be only visible to you. You can select a course(eg: Pretzel) and set the bot’s tempo at a certain watt/kg initially and then you can draft the bot. The pace can be changed through the zwift mobile companion app or through the keyboard.
This can be used as a practice for motor pacing. Higher the speed, more important is the draft so for instance you are on the sand and sequoias course and set the bot’s tempo at 4.0w/kg, the bot will cruise at that pace and you need to draft the bot.
You can also get used to riding with someone stronger than you at anytime you wish!
Lastly if the bot drops you(if the gap is 2 seconds minumum?), you have the option of the bot easing off for you at a certain w/kg which you set initially or you can bring back the bot.