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??? (Hyperdeath)
This soul is owned by TotallyNotJames
This soul is a different version of DETERMINATION. This soul can slowly heal you if you have low EXP.
The EXP part is slightly irrelevant as this is how EXP works in Deltarune:
EXP is a property in Deltarune. It is implied to, like its Undertale appearance, be gained by killing enemies.[5]
In Chapter 1, after completing a battle, the game always says that the party earned 0 EXP, regardless of how the enemies were defeated. In Chapter 2, if any enemy is defeated violently during an encounter, the game simply displays the amount of D$ received along with "You became stronger" (or "Noelle became stronger" if she is present) instead of specifying that 0 EXP was earned, implying that EXP was earned.
In the Dark World, EXP is not displayed anywhere, so even if EXP is earned, this is not visible. In the Light World, EXP is displayed, but this value is entirely unconnected from the Dark World.