[Dragokas]

Well, technically IsValidPointer() is quite time consuming operation if it is done like 100 times per frame.
Also, on linux MemoryEx delays server start for 1 sec., but that's only after server restarting.
I'm working under optimization.

However, I'm curious if returning false result from GetPosAtHeight might cause something @yzybb described.
As I can see, it is get called from ChaseVictim::AvoidNeighbors which is related to behaviour after spawning, not before.