How does Prospero create problems in the plot that Caliban has hatched in The Tempest?
In order to disrupt the plot that Caliban has hatched against him, Prospero does two main things. First, he uses the conspirators' greed against them. Second, he uses his magical powers to attack them.
The first thing that Prospero does is to have Ariel hang up all his really nice kingly clothes on a line. When the conspirators come, they start to steal the clothes instead of killing Prospero like Caliban wants them to. By doing this, Prospero uses their greed against them.
After that, Prospero and Ariel set spirits disguised as dogs on the conspirators to drive them away.