Tā miáohuì de wèilái bùguò shì yī ge měilì de huànjǐng.
The future he describes is nothing more than a beautiful illusion.
Tips
usage
Compare with 幻象 (huànxiàng) which leans abstract/mental, and 海市蜃楼 (hǎishìshènlóu) the classical chengyu for a mirage. 幻景 emphasizes the visual scene that turns out not to be real.
