First used: Episode 21.
Owner: Warrior Goddess; All; Self.
Type: Sword; Guardian.
Bio: Years ago, the Sentinel Knight used his own power to contain Thrax, son of Rita Repulsa and Lord Zedd, in a Space Dumpster and placed him on Earth's Moon. But by doing so, the Sentinel Knight grew weaker. With Sentinel Knight in a weakened state, years later, Thrax was able to break free from his confinement. Thrax proposes a temporary evil alliance to eliminate the Rangers.
The evil alliance overpower the rangers. They give their evil energy to Thrax, which he then attacks the Universal Morphing Grid. The Team's Trackers are damaged, and they are no longer Power Rangers. Sentinel Knight appears, and Thrax tells his evil alliance that they can't destroy him, but knows what can. Sentinel Knight transports the team away. Sentinel Knight knows he must do something now that the remaining jewels are unprotected. Sentinel Knight forms a new team of Power Rangers to replace them: Green Mystic Ranger (Xander); S.P.D. Red Ranger (Bridge); Yellow Dino Thunder Ranger (Kira); Blue Wind Ranger of Ninja Storm (Tori); Mighty Morphin Black Ranger (Adam).
Adam assists Andrew with working on trying to repair the Trackers. Andrew was able to reinforce the Morphing Grid so it can't cut off their powers as well. Adam tells him that he may know who might be capable of fixing the Morphing Grid.
Episode 21: Adam brings his four team members with him to a warehouse in Angel Grove. The team finds what Adam was looking for, and they bring it back to base.
Mack asks Sentinel Knight what Thrax meant when he said he knew what could defeat Sentinel Knight. He tells Mack their is one weapon that has the power to destroy him, the Sword Excelsior.
Rose has returned to her university. Mack shows up and asks her what she knows about the sword called Excelsior. She tells him there is a book all about it in the library. Mack takes off to search for that book. But Rose knows something is up, so she makes some calls.
Mack finds a statue holding Excelsior. Thrax has been following Mack, leading him right to Excelsior. The other five former OO Rangers arrive at the scene. From out of a crate, Andrew and Adam reactivate Alpha 6. Thrax plans to restore his parents' legacy by destroying the Sentinel Knight. Thrax tries to grab Excelsior, but the statue doesn't allow him. Mack explains that Excelsior belongs to the Warrior Goddess, and only she can release the sword. Now that he knows he can't have the sword, Thrax just decides to trash the entire planet. Andrew and Adam transport Alpha 6 into the Morphing Grid, though no one has ever been inside. Warrior Goddess appears as the statue and hands Mack Excelsior.
Back in the base, Mack gives Excelsior to the Sentinel Knight. The Sword's power is so great that it not only restores his power, but also becomes a part of him, transforming his whole body. Alpha 6 returns to the base, and has repaired the Morphing Grid. The OO Rangers now have their powers back.
The evil alliance prepare for battle. The team of eleven Rangers morph back into action.
Mighty Morphin Black Ranger takes on Thrax alone. Excelsior joins the battle, transforms into Sentinel Knight and destroys Thrax with a
power kicking attack. The evil forces retreat.
Sentinel Knight can also fire a powerful blast from the chest and grow zord size.
Super Power Punch.
Episode 32: With the villains destroyed, Sentinel Knight appears in his true form with the crown, no longer combined with the sword Excelsior.