The devil does create things in attempting to be like God. He has been at this since the beginning.
Isa 14:13 For thou hast said in thine heart, I will ascend into heaven, I will exalt my throne above the stars of God: I will sit also upon the mount of the congregation, in the sides of the north:
Isa 14:14 I will ascend above the heights of the clouds; I will be like the most High.
Isa 14:15 Yet thou shalt be brought down to hell, to the sides of the pit.
Isa 14:16 They that see thee shall narrowly look upon thee, and consider thee, saying, Is this the man that made the earth to tremble, that did shake kingdoms;
Its fair to say he is creates mayhem, death and lies. The he also perverts many other things including signs and wonders.
Joh 8:44 Ye are of your father the devil, and the lusts of your father ye will do. He was a murderer from the beginning, and abode not in the truth, because there is no truth in him. When he speaketh a lie, he speaketh of his own: for he is a liar, and the father of it.
Joh 10:10 The thief cometh not, but for to steal, and to kill, and to destroy: I am come that they might have life, and that they might have it more abundantly.
He also creates lying signs.
2Th 2:8 And then shall that Wicked be revealed, whom the Lord shall consume with the spirit of his mouth, and shall destroy with the brightness of his coming:
2Th 2:9 Even him, whose coming is after the working of Satan with all power and signs and lying wonders,
2Th 2:10 And with all deceivableness of unrighteousness in them that perish; because they received not the love of the truth, that they might be saved.
I don't think any of these false signs would be healings because all healings destroy the works of the devil.
Act 10:38 How God anointed Jesus of Nazareth with the Holy Ghost and with power: who went about doing good, and healing all that were oppressed of the devil; for God was with him.
These false miracles will also not be casting out devils.
Mar 3:23 And he called them unto him, and said unto them in parables, How can Satan cast out Satan?
Mar 3:24 And if a kingdom be divided against itself, that kingdom cannot stand.
Mar 3:25 And if a house be divided against itself, that house cannot stand.
Mar 3:26 And if Satan rise up against himself, and be divided, he cannot stand, but hath an end.
Mar 3:27 No man can enter into a strong man's house, and spoil his goods, except he will first bind the strong man; and then he will spoil his house.
Mar 3:28 Verily I say unto you, All sins shall be forgiven unto the sons of men, and blasphemies wherewith soever they shall blaspheme:
This is what Henry says about the Devil's signs. He speaks well in identifying thier support of doctrines that do not magnify Christ.
Matthew Henry's Concise Commentary
2:5-12 Something hindered or withheld the man of sin. It is supposed to be the power of the Roman empire, which the apostle did not mention more plainly at that time. Corruption of doctrine and worship came in by degrees, and the usurping of power was gradual; thus the mystery of iniquity prevailed. Superstition and idolatry were advanced by pretended devotion, and bigotry and persecution were promoted by pretended zeal for God and his glory. This mystery of iniquity was even then begun; while the apostles were yet living, persons pretended zeal for Christ, but really opposed him. The fall or ruin of the antichristian state is declared. The pure word of God, with the Spirit of God, will discover this mystery of iniquity, and in due time it shall be destroyed by the brightness of Christ's coming. Signs and wonders, visions and miracles, are pretended; but they are false signs to support false doctrines; and lying wonders, or only pretended miracles, to cheat the people; and the diabolical deceits with which the antichristian state has been supported, are notorious. The persons are described, who are his willing subjects. Their sin is this; They did not love the truth, and therefore did not believe it; and they were pleased with false notions. God leaves them to themselves, then sin will follow of course, and spiritual judgments here, and eternal punishments hereafter. These prophecies have, in a great measure, come to pass, and confirm the truth of the Scriptures. This passage exactly agrees with the system of popery, as it prevails in the Romish church, and under the Romish popes. But though the son of perdition has been revealed, though he has opposed and exalted himself above all that is called God, or that is worshipped; and has spoken and acted as if he were a god upon earth, and has proclaimed his insolent pride, and supported his delusions, by lying miracles and all kinds of frauds; still the Lord has not yet fully destroyed him with the brightness of his coming; that and other prophecies remain to be fulfilled before the end shall come.