Make sure to check changelogs for any new changes!
Deer are hooved entities based on their real-world counterpart.
They are more passive rather than actual deer known in the real-world. They are still alert and sometimes apprehensive, though if approached nicely they will gain your trust.
Basically, the same physiology and structure as the deer from the real-world.
Approach carefully.
Scare them.
Attack them.