The Yalex are a species of gigantic spider-like creatures. They are known for gestating the rare and valuable Yalexian Pearl. The Paladins of Voltron battled a Yalex on the moon of Krell that had a clouded eye that served as a Yalexian pearl.
They have four red legs which they use in conjunction with three pairs of translucent, purple wings to move around in the vacuum of space.
Yalex hibernate inside moons and other small, celestial bodies, and only emerge voluntarily to feed. They can sustain themselves for eons by swallowing stranded spacecraft and keeping their body temperatures low.
They are very territorial, and will attack with dozens of dagger-sharp teeth and spiny forelegs if they are attacked. It's difficult to determine if a moon is presently inhabited by a Yalex, but previously inhabited moons can be identified easily as they will be surrounded by debri, and the moon hollowed out.
The Yalexian Pearl grows inside the Yalex's thorax and once it's fully formed, it breaches the skin and provided the creature with 360 degree vision. The Pearl is invaluable to the Yalex because without it, they are rendered vulnerable to animal poachers and developers who seek to make Yalex moons habitable for other species. They have eight, purple glands which shoot purple lasers as a mechanism to defend the Pearl. The immense danger acquiring the Pearl poses is what makes it so valuable.
- Yalex basically was an awakening beast that was fated to destroy the moon of Krell.