A leading Saudi cleric has urged followers to shun Pokemon Go.
Sheikh Saleh al-Fozan said a fatwa (religious ruling) issued against an earlier Pokemon card game also applied to the new mixed-reality app.
The 16-year-old edict said the game contained "forbidden images" and violated an Islamic ban on gambling.
Pokemon Go, first released on 6 July, is proving popular in the Middle East despite not having officially launched there yet.
The game has proved so popular that Nintendo - which owns a stake in the Pokemon Company - has seen its shares double in value.
The game challenges players to visit real-world locations to catch cartoon monsters, which can be seen superimposed over views of the surrounding area shown on a smartphone screen.
The fatwa was originally issued in 2001 by the General Secretariat of the Council of Senior Religious Scholars, to which Sheikh Saleh Al-Fozan belongs.
It states that the ability to mutate the creatures to give them more power amounts to blasphemy as it promotes the theory of evolution.
In addition, it objects to the use of a symbols and logos of "devious religions and organisations".
"The six-pointed star... is associated with Judaism, the logo and sign of the state of Israel, and the first symbol of the Masonry organisations in the world," it says.
"The game contains many forms of the cross which is the symbol of Christians."
It also highlights symbols it says are linked to Masonry and the Shinto religion.
Fatwas are legal edicts. They depend on who is saying them and the general acceptance by the rest of the scholars.
This means that any scholar can pronounce a fatwa, but its influence might not carry beyond that particular scholar's territory.