ok beforehand i just wanna say how do some people HATE alien stage ships but love onethrees dynamic... its almost the same as ivantill but tweaked </3 so i believe that one had a good motive but didnt know how to handle it properly, which makes sense because she was trapped for many years and barely ever properly socialized with anyone, making her task to save three very obsessive and toxic. since she never got to fully see and understand how three was effected by her actions, she thought three would be open to one saving her. but because of her isolation and psychological torture that followed that isolation, she became very dead set on saving three without knowing that three didnt want anything to do with her. "oh but one should've known how to deal with it before she was in the moon!!" she was still isolated??? did you even watch ALONE?? one was IGNORED and didnt have proper interactions with the other numbers before the whole incident with three, so she WOULDNT have known how it would affect three. anyways, one definitely wanted revenge on the other algebraliens but again so obsessed with three that she didn't know what the limit to how bad she was becoming was. just to add another note, i do not condone her actions in tpot 25 but i also understand them. the contestants and algebraliens were kind of hypocritical as three did kill fifteen and nobody seemed to care because three was injured and paranoid, which doesnt matter because one did the same thing and got a huge punishment. you can also infer that they forgave three for murdering fifteen because she recovered fifteen soon after, but that was exactly what ones main objective was and she still got hated and immaturely punished. which comes to my next point. the algebraliens at the time of the incident acted very childish and young, which you can assume that they still havent really matured much since. they also didnt have powers and werent prepared or used to death before. you can also tell that the algebraliens made a very quick decision to put one in the moon and hadnt fully thought it through. in all honesty, they shouldnt have let four decide the punishment. back to tpot 25, i feel like three shouldve somewhat heard one out and understood the moment from ones perspective. her action to immediately kill one was not very logical, and it just shows how much more toxic one and threes relationship is. i feel like onethree wouldve been a very happy and healthy relationship if three waited and didnt share ones secret with everyone about the powers until one was prepared to interact with the others. its really sad to see how they were so happy together and one finally made a friend just for three to basically backstab her and betray her trust. yes, one killing three over it was an overreaction, and you can see how one notices that after she kills three, but one was really upset that the only friend she made shared her biggest secret that was only meant to be shared between them. i cant really think of what else to say so yeah
tldr: onethree is toxic doomed and obsessive but wouldve been really positive if three kept the powers a secret until one was ready