Elves have pointed teeth, small, delicate genitals and the ability to vomit up plants once per day.They are itinerant disease ridden vagrants who have fucked the world so bad that it would take the destruction of every living thing on the planet to fix it. They are burned by holy water.
Elves have spell slots. They can use them for spells and inventing plants. Once they have invented a plant they can vomit up a corresponding seedling once per day. If they ever clear out the spell slot then that entire species of plants will wither and die.
Elven children can be made the same way as plants. Elves can also reproduce sexually and through the implantation of humans with changeling children, but they prefer not to. Natural birth kills elven mothers and changelings creep everybody out - even elves.