Most of the short Greys are programmed lifeforms created by an insectoid race. Some groups are negatively-polarized, some are positively-polarized, and some are amoral. Other extraterrestrials have since appropriated these programmed lifeforms, and they are now ubiquitous.
The Tall Greys are about 8 feet tall. They have a treaty with the U.S. government. They are allowed to abduct people as long as they share a list of abductees.
- “Corey Goode - Secret Space Programs & Break Away Civilizations” https://youtu.be/7Kk1J2XNoBU