|This show ran on the USA Network for 40 episodes, shortly after the "Mighty Morphin Power Rangers" franchise grew.
Focusing on four "teenagers", Laurie, Gordon, Drew, and Swinton being recruited by an blob-like alien called Nimbar. To fight off the monsters sent by Emperor Gorganus, and his talking bird friend, Lechner.
In the first episode Nimbar recruits four "teenagers", and with a touch by his "finger" gives them each a tattoo from the Zodiac. When their tattoo flash, this means he needs them and a portal appears near them to go his underground lair-like place.
To become their sentinel form, they step on a platform, AKA the Transo Discs (in the lair) and each yell out their sign. Laurie is Scorpio (Aqua/Light Blue-ish), Gordon is Taurus (Black), Drew is Centaur (Purple), and Swinton is Apollo (Yellow). When putting their hands together (in square) they form the ultimate sentinel, Nitron!
This was really a low-budget kid show, which the Emperor Gorganus was made up from what looks like old rubber Halloween like costumes. His side kick, Lechner a talking bird is made out of rubber, too.