When this creature enters, if you control a tapped creature, create a 1/1 white Warrior creature token with vigilance.
If you don’t control a tapped creature as Supply Caravan enters the battlefield, its ability doesn’t trigger, even if you can tap a creature right away. If you control no tapped creatures as the ability resolves, nothing happens.
If an effect causes Supply Caravan to enter the battlefield tapped, it will satisfy its own triggered ability.
