Lieutenant Penumbra

Lieutenant Penumbra is a lieutenant in the Moonlanders' army.

Penumbra is a lieutenant working under General Lunaris' command within the hidden city of Tranquility on the moon. She is the first of the Moonlanders to have discovered Della within the "deserted" section of the moon, and later fights along side her and Lunaris against the Moon Mite. During the fight, Penumbra insists on sacrificing Della to kill the monster. Due to the destruction of Della's ship, Penumbra and Lunaris bring her to their hidden city, where Penumbra gloats about their main resource of gold being a super common thing.

While Della's back was turned, Penumbra expressed her dissatisfaction to Lunaris of allowing an earth inhabitant to roam free around their city. But Lunaris countered her argument by stating how she was able to beat one of their biggest enemies as if it was nothing, leading him to believe that she could be useful. On her part, Penumbra suspected Della might become a danger.

During Della's stay within Tranquility, Penumbra had continued to grow suspicions on Della working on her mysterious project, believing her to be a liar with a darker motive. She further proceeded with her complaints to Lunaris, but this instead caused her to become roommates with Della instead until she finishes working on her rocket. As Della was nearing her completion of the rocket, Penumbra shouted to her people in anger that if they love how much earth sounds, then they should just go there themselves.

She also noticed many of her people intrigued by her knowledge of Earth and even requesting that they visit, but still saw her words as lies and attempted to belittle her because of it. Nevertheless, Della swore to find a way for everyone to come to earth, angering Penumbra even to a point of splitting her own spear into two. Later as Penumbra continued to show her frustration with Lunaris, Della visited them and even returned Penumbra's spear which she fixed for her. Della even admitted to Penumbra that no one could protect her people as well as she could, but still promised to do her best. This warmed up Penumbra's feelings to Della, but she still believed it wasn't a good idea to send her people to earth.

Instead, she decided to bring Della over to her ship and activate it to the point where the engine couldn't be shut off manually. Penumbra then woke the unconscious Della and claimed that the ship was malfunctioning. This prompted Della to regretfully leave earlier than expected, but also giving Lunaris the manual to building rocket ships, surprising Penumbra. As Della was taking off, Penumbra was also surprised to see that Lunaris had shot himself, only for her to realize that he did so in order to manipulate the other Moonlanders into believing that Della had betrayed them, and decided to stage an invasion on planet earth.

Penumbra questioned Lunaris on his decision, with Lunaris only replying that he wanted to give their people a reason to fight. With Penumbra worrying about the sake of their citizens and believing he was only doing this for his own personal reasons, Lunaris shouted back by claiming he wasn't going to be living in fear like his father, and that he intended to ensure planet earth feared him instead.

Later, after Della's brother, Donald crashes on the moon and is captured, Penumbra is promoted to Captain by General Lunaris for having "captured the traitor's brother." Penumbra points out that it's a lie, but Lunaris merely dismisses it to the others.