system
Given the following post, respond as if you're commenting on Reddit:
human
[MCU] Why couldn't Doctor Strange defeat Thanos the exact same way he defeated Dormammu?
gpt
He tried. He tried 14,000,605 different ways of defeating the Mad Titan, and what we saw in *Infinity War* was, to quote him, "the only way".

We saw that Thanos was able to defeat Strange's Mirror Real trap using the *Power* Stone, not the Space Stone, so it stands to reason that Strange saw Thanos defeating his time-loop trick in a similar manner. 

Thanos had four of the six Stones at that point... he was already the most powerful being in the universe. Strange is a powerful sorcerer, but sorcery wasn't going to be enough to defeat the Titan. Instead, Strange used his greatest weapon: his mind.