Complex sentence: The 24-man animation team was split into two groups, half assigned to the creation of the fifteen new CGI creatures which would populate "noitulovE" (in Maya), while the other half was to create the backgrounds (in Houdini).
Split into simpler sentences: The 24-man animation team was split into two groups. Half were assigned to the creation of the fifteen new CGI creatures populating "noitulovE" (in Maya), while the other half created the backgrounds (in Houdini).