Illusionary magic, is when things are manipulated in a way that causes someone to think that what he sees is actually that way, while it is not true.
Illusionary magic are like fake tricks that have no truth in them, and they are like the magic of Fir'awn's (Pharoah's) magicians. Allaah, the Most High, has said:
"He (Moosa) was made to believe from their magic that they (the magicians' sticks) were (snakes) moving about" [Qur'an 20:66]
And Allaah, the Most High, has said:
"The put magic on the eyes of the people and sought to frighten them." [Qur'an 7:116]
[Even illusionary magic can be considered disbelief in Allaah. Shaykh Saalih al-Fawzaan, may Allaah preserve him, says in his book, Duroos Fee Sharh Nawaaqidh al-Islaam (p.146-147)
Jundub ibn Ka'b, the Companion, killed a magician in the presence of one of the governors of Banee Umayyah. He came and found the magician playing games in front of the governor, pretending to kill a person and then bring him back to life by cutting off his head and then replacing it. This is kind of illusionary magic. He was trying to convince the people that he was killing him and putting his head back upon his shoulders. He did not actually do anything, he was only tricking the people with an illusion. So Jundub went up to him and struck him with his sword until he chopped his head off, and said,
"If he was truthful, then let him bring himself back to life"
Ibn 'Abdil-Barr (may Allaah have Mercy on him) mentioned that the governor was al-Waleed ibn 'Uqbah (may Allaah be pleased with him) and that he arrested Jundub for this action and wrote to the khaleefah 'Uthmaan ibn 'Affaan (may Allaah be pleased with him) about what happened. 'Uthmaan the ordered him to be released and he was. (Alistee'aab, p.113)]