Saying that the music on Mirage is Prog would be stretching it quite a bit. Psychedelic Pop would be a better description.
The first 6 songs are all in the 2 to 5 minutes range and really have a sixties "wall of sound" feel to them, with some cool instrumentation but almost always with the presence of vocals. On this subject, the singing is very good, often featuring some harmonies, somewhat reminding me of The Byrds.
The next three songs are more acoustic and a pretty faithfull cover of The Beatles "Norwegian Wood" is offered. To my taste these songs are even better then the more electric ones.
Finally, the album concludes with a 10 minutes instrumental very much in the New Age genre.
Mirage by Elf Project offers a nice collection of songs that should appeal to fans of the sixties Pop/Psych sound. It is a very good album, but I would not recommend it to Death Metal fans, unless they have a huge opened mind.