One Evangelical Christian sums it up with, Prayer should not be spellcasting. God is not your djinni.
Throughout the NT believers are encouraged to always remember that we are fighting a battle against the forces of evil. The term "Spiritual Warfare" is generally used by those who acknowledge and undertake to accept this calling, "enduring hardness, as a good soldier of Jesus Christ".
Regarding comparisons to "black magic", I would lovingly wish to draw your attention to Jesus' response to similar accusations He faced in Matt 12:22-32. In light of these words from Jesus such terms should not be bandied about since the implications are so very severe.