Exodus 7

As Moses was commanded to perform a miracle before Pharaoh -

"...Aaron cast down his rod before Pharaoh, and before his servants, and it became a serpent.
11 Then Pharaoh also called the wise men and the sorcerers: now the magicians of Egypt, they also did in like manner with their enchantments.
12 For they cast down every man his rod, and they became serpents: but Aaron's rod swallowed up their rods."  (Old Testament | Exodus 7:10 - 12)

Obviously then, Satan and his Legions have the capacity to perform miracles in order to deceive for John saw -

"For they are the spirits of devils, working miracles, which go forth unto the kings of the earth and of the whole world..."  (New Testament | Revelation 16:14)

President Joseph Fielding Smith taught -

“All down through the ages and in almost all countries, men have exercised great occult and mystical powers, even to the healing of the sick and the performing of miracles. Soothsayers, magicians, and astrologers were found in the courts of ancient kings. They had certain powers by which they divined and solved the monarch's problems, dreams, etc. One of the most striking examples of this is recorded in Exodus, where Pharaoh called ‘the wise men and the sorcerers’ who duplicated some of the miracles the Lord had commanded Moses and Aaron to perform. When Aaron threw down his rod, it became a serpent. The Egyptian magicians threw down their rods, and they also became serpents….

“The Savior declared that Satan had the power to bind bodies of men and women and sorely afflict them [see Matthew 7: 22– 23; Luke 13: 16]. If Satan has power to bind the bodies, he surely must have power to loose them. It should be remembered that Satan has great knowledge and thereby can exercise authority and to some extent control the elements, when some greater power does not intervene.” (Smith, Answers to Gospel Questions, 1: 176, 178.)

But, the power of God or the priesthood is greater than the powers of Satan where "Aaron's rod swallowed up their rods" and will always be greater when exercised.  Mormon taught -

"For behold, the Spirit of Christ is given to every man, that he may know good from evil; wherefore, I show unto you the way to judge; for every thing which inviteth to do good, and to persuade to believe in Christ, is sent forth by the power and gift of Christ; wherefore ye may know with a perfect knowledge it is of God.
17 But whatsoever thing persuadeth men to do evil, and believe not in Christ, and deny him, and serve not God, then ye may know with a perfect knowledge it is of the devil; for after this manner doth the devil work, for he persuadeth no man to do good, no, not one; neither do his angels; neither do they who subject themselves unto him."  (Book of Mormon | Moroni 7:16 - 17)

Miracles performed by Satan will only bring darkness.