9.12.2 Rudhir and the cat.

It was a trap, an unexpected one as he barely understood the nature of his opponent until he was caught. It was past and the path of Transmutation and illusion was barely developed. The majority of mages at this time were arcanists, and their mind was too limited to what the term element even meant. 

They haven't explored the micro-universe that was the building blocks of the world, which can be seen from their simpler spells that lacked firepower in Farhad's eyes. It would be appropriate to call these spells just manipulation of elements on the surface level. 

So why did he fall for it? Obviously Farhad, after learning the goal of Lord Dilbur, there was no need to struggle too much. Killing will only get you farther than the goal and turn the whole scenario chaotic. So it's better to play along the game and learn the situation at his own pace.