World of witcher is filled with different monsters and monstrosities, every single one is different than the other, they all act random, they are pretty lethal, wise witcher always checks his monster book before going into fray.
There are several monster families.
Necrophages[]
These enemies are susceptible to Necrophage Oil.
Specters[]
These enemies are susceptible to Specter Oil.
Beasts[]
These are some typical nature creatures they are not such big danger in the game, just be careful of the wolf packs.
Bear
White Wolf
Wolf
Wild Dog
Cursed Ones[]
These enemies are susceptible to Cursed Oil.
Hybrids[]
These enemies are susceptible to Hybrid Oil.
Insectoids[]
These enemies are susceptible to Insectoid Oil.
Elementa[]
These enemies are susceptible to Elementa Oil.
Relicts[]
These enemies are susceptible to Relict Oil.
Ogroids[]
These enemies are susceptible to Orgoid Oil.
Draconids[]
These enemies are susceptible to Draconid Oil.
Vampires[]
These enemies are susceptible to Vampire Oil.