I can only guess on this one. Based on reading his dialog through the the first arc, I started to realiozed he judged us wizards too quickly and perhaps he thought we were not good enough to save Wizard City and only getting in the way?
As showed on the last B.O.X. (avalon one): Cyrus, Malistare and Sylvia Drake were best friend; Especially Malistare and Silvia who later will be married.
All the 3 will leave dragonspyre to wizard city and will teach the 3 spirituals school. But Silvia die and Malistare become crazy and (as a death wizard) start to search a way to respawn his love.When Merle Ambrose try to free him from his obsesion he hide the school of death and flee Wizard city.
Cyrus is now lonely; angry against his brother to let him on WC; against Merle Ambrose for his brother betrayal and against all young wizards and witches that continue to learn magic like nothing has happened.
Cyrus still refuse Sylvia's death and a part of him want to see Malistare return with Sylvia but he know someone must stop his Brother too and the student who started to stop Mali's associate on WC is a real danger for his hope.
Cyrus is not Snape.
For me Cyrus and Malistare together can be compared to Snape. Cyrus can be compare to the face snape show to hogwart but the real motivation is Malistare.
Thats my point of view i'm not someone of the development team so i maybe wrong.
Kane and Erin GoldenFlames, Diviner and Theurgist.