Beforian

The Beforians are a humanoid alien species that inhabited in semi-dying planet named Rugaro, which was near the Dark Zone and ultimately became extinct.

Biology
They are slender build humanoids with a single black eyes, a glowing antennas on top of their heads, and green tentacles that extend from the top of their heads into their mouths.

History
At some point, the Beforians were assigned to guard the fifth dimensional key. When their home planet began to die from a black hole called the Dark Zone, they decided to send the key into cosmos where it will not be destroyed but the ceremonial ritual was interrupted by an notorious intergalactic criminal Sheryl Goodpseed. She kills the guardian and picks up the key causing a chain reaction causing the death of the Beforian race.