So I was thinking about Undertale and Deltarune and I think we have a fundamental misunderstanding of the Red soul. Firstly All Souls have at least some Determination (DT) as was stated in the True Lab and how they got enough DT to “create” Flowey. True the Red soul has the most DT however I do not believe that is their true trait. The main reason we think the red souls trait is Determination is because of the flag game in Snowdin, however there is already a soul who’s trait is a synonym to determination, Perseverance, it seems odd that there would be 2 souls with such similar traits. Now in Undertale it is implied by the true pacifist ending if you re-enter the game, Flowey asks you to please let them have their happy ending, meaning you, the player were controlling frisk, also in Deltarune the red soul is controlling Kris. All of this to give my idea, the red souls trait is not Determination it is Control.
